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How to Maximize Concurrent Training

How to Maximize Concurrent Training
By Marc Lewis

Simultaneously training for adaptations associated with resistance and endurance training (RT & ET), otherwise known as concurrent training (CT), is widely debated by fitness professionals and strength coaches alike. CT has been criticized due to the potential for chronic overreaching, as well as the competing adaptations associated when performing RT and ET, concurrently. However if programmed carefully, CT can produce a lean and sculpted physique, while obtaining a high level of fitness as measured by health aspects as well as athletic parameters. Therefore, the purpose of this article is to elucidate the ways in which the adaptations associated with both RT and ET can be maximized when training concurrently.

In 1980, Dr. Robert Hickson introduced the concept of “interference” when training for adaptations associated with both RT and ET simultaneously (1). Currently, it is generally accepted that you cannot fully maximize skeletal muscle hypertrophy, strength, and power, while engaging in an aggressive ET program. Nevertheless, there is a growing body of literature supporting the theory that high-intensity RT not only does not impede adaptations associated with ET, it can actually improve endurance performance (2-11). Furthermore, it has been postulated that ET may not significantly blunt adaptations associated with RT, and can accelerate a reduction in fat mass as well as improve sleep, and cardiac efficiency (12-15).


The Interference Theory

As previously mentioned, the interference theory originated from some pioneering research by Dr. Robert Hickson in 1980. Dr. Hickson investigated the training affects of a high frequency, high volume CT program, which utilized running as the ET modality and compared it to strength or endurance training alone over a ten-week period (1). Dr. Hickson found that strength increased in the CT group until approximately weeks 6-7, which was followed by a “leveling-off period” and a sharp decrease in strength the final two weeks (1). Additionally, Dr. Hickson noted no statistically significant differences in aerobic capacity between the ET only group and the CT group. Nevertheless, there were a couple of interesting outcomes associated with body composition. The CT group decreased their body fat significantly (p <0.05), and to a greater extent than either the ST only or ET only groups (1). Furthermore, the CT group increased their thigh girth 54.7 to 56.4 cm (p <0.05), which was similar to the strength only group 53.3 to 55.5 cm (p <0.01) (1). This is an indication of type I muscle fiber hypertrophy, which is commonly seen in certain endurance athletes such as cyclists or cross-country skiers.

Dr. Hickson’s results provided the foundational research concerning the inference phenomenon, while setting the platform from which many other investigations were launched. Rather than discuss every significant study conducted in the past 35 years, this article will provide you with the rationale for competing adaptations, discuss the benefits associated with RT and ET alone, as well as provide a set of practical recommendations to maximize RT and ET adaptations when training concurrently.

Inference Effects and Competing Adaptations

Two points are crystal clear from the current literature: 1) inference effects are multifactorial, and 2) there is a dose-response relationship between ET volume (i.e. frequency & duration) and its potential negative effects on RT outcomes. Interference is thought to be a combination of chronic overreaching, which can lead to overtraining, and long-term competing adaptations at the cellular level (16). In addition, the dose-response relationship that exists with increased ET volume does not appear to exist to the same extent with RT volume when examining endurance outcomes (i.e. VO2max, aerobic enzymatic activity, etc) (2-11). In fact, RT has been shown in numerous studies to improve endurance performance directly (i.e. time trial) (8, 17), as well as endurance parameters (VO2max and running/cycling economy) (2-11, 17). Furthermore, high-intensity RT (loads >85% 1RM) paired with explosive, high velocity RT has been suggested to be a superior method of RT in recreationally trained, highly trained, and elite endurance athletes (3-6, 8-9, 12, 18).

Chronic overreaching, and ultimately overtraining, is theorized to be a product of high volume, high intensity, and/or high frequency training bouts over an extended period of time (16). This theory is generally termed the “chronic hypothesis,” and is limited in its literary support. These effects are suggested to be exacerbated when the training bouts involve large muscle groups and excess exercise-induced muscle damage, as seen in repetitive eccentric contractions (i.e. running) (12, 16). ET has a natural high volume component, therefore, when combined with high volumes of RT it can be suggested that an overreaching stimulus could be created over time (12, 16). Therefore, when structuring a CT program it can be theorized that strategically programming ET around RT would be most effective for maximizing adaptations concurrently.

Aside from chronic overreaching, some researchers have put forth an “acute hypothesis,” which contends that residual fatigue from the endurance component of CT compromises the ability to develop muscular tension during the RT component (16). According to this theory, the tension generated by the working musculature during RT would not be sufficient enough to maximize strength development (16). In addition, proponents of this theory have suggested that performing RT directly preceding ET can alter endurance performance due to residual fatigue (16). Therefore, the acute hypothesis focuses on the scheduling of training sessions as the main interference effect associated with CT, as opposed to simply training concurrently (16).

RT Adaptations

RT adaptations can be broadly described as increases in muscular hypertrophy, strength, and power.

Muscular Hypertrophy: Exercise-induced muscular hypertrophy is centered on the mechanistic or mammalian target of rapamycin (mTor) signaling molecule, which demonstrates increased activity post-RT (20-21). mTor exists in two complexes, but for the purposes of this article we will only focus on mTor1. Increased mTor1 activity results in an increase in protein synthesis through a cascade of intracellular transduction pathways triggered by a mechanical tension/overload stimulus (19). Furthermore, amino acids (specifically leucine) have been shown to increase protein synthesis predominantly by increasing the primary leucine transporter (LAT1), which acts to up-regulate mTor1 (22). Therefore, this would theoretically result in an increase in the cross sectional area (CSA) of the muscle fiber, which directly relates to muscular strength.

Muscular Strength: Muscular strength is a combined effect of neural activation, muscle fiber size, and connective tissue stiffness (2-11). Neural alterations elicited by RT include an increased neural drive, selective activation of motor units (MUs), increased motor unit synchronization, increased rate of force development (RFD), increased inhibition of golgi tendon organs (GTOs) (termed autogenic inhibition), and a reduced antagonist inhibition (2-11, 23). Neural alterations elicited by RT do not appear to be significantly altered by ET, although repeatedly engaging in high-intensity ET could play a role in the milieu associated with neuromuscular fatigue, and/or factor into chronic overreaching (16). Additionally, changes in motor unit recruitment could reduce patters associated with maximal voluntary contractions, which could partially explain reductions in power parameters discussed by Wilson et al (2012) (12, 16). However, these effects should only be considered significant if concurrently training a power sport athlete. Furthermore, there is no research indicating that CT has detrimental effects on connective tissue stiffness, but one could surmise that without chronic overreaching, or an energy deficit, connective tissue stiffness should not be negatively altered by CT.

Muscular Power: Muscular power (force x distance/time) is simply rate of performing work, which can be described as the product of force and velocity. Improvements in muscular power rely primarily on neural alterations, specifically increases in RFD and motor unit synchronization, as well as a reduced antagonist inhibition. A meta-analysis by Wilson et al (2012) suggested that decrements in muscular power may be more likely associated with CT than decrements in either strength or hypertrophy. However, there is a clear dose-response relationship between the volume of ET, and decrements in muscular power (12). Therefore, it can be theorized that individuals wishing to maximize muscular power should limit the volume of ET performed when concurrently training. Furthermore, it can be suggested that performing cycling or rowing for endurance exercise can preserve RT associated adaptations when compared to running (2, 10, 12, 16).

ET Adaptations

ET adaptations can be broadly described as improvements in cardiovascular, muscular, and metabolic function.

Cardiovascular: ET elicits a multitude of cardiovascular adaptations that assist in improving blood flow and delivery. These adaptations include an increase in stroke volume (SV), an increase in heart size (termed cardiac hypertrophy), an increase in cardiac output (due to an increased SV), and a decrease in sub-maximal heart rates for a given intensity. RT has been shown to have a positive impact on exercise capacity (i.e. VO2max) when concurrently training, while initiating a physiological form of cardiac hypertrophy- read more here. These cardiovascular adaptations can have positive impacts on RT training (i.e. work capacity) and recovery, as well as improve cardiac efficiency.

Muscular/Metabolic: ET initiates a variety of adaptations in active skeletal muscle, which include increased mitochondrial volume and density, increased capillary density, and improved fat and glucose oxidation. In addition, there are muscle fiber type transitions that occur as type IIx fibers become more oxidative and resemble type IIa fibers. This muscle fiber transition could theoretically reduce the power output and force per unit of area of the muscle fiber, since myosin heavy chain isoform content of type IIx – IIa – I muscle fibers differ considerably, and have been correlated with various strength indices (16). However, current literature investigating CT has reported little difference in fiber type change between the CT groups and the RT only groups (16). RT training that results in an increase in muscular hypertrophy can blunt the increased capillary density, or decrease capillary density through the increase in CSA. However, unless you are a competitive endurance athlete this should not be a concern. This result can be negated by focusing on high-intensity, low volume RT with loads >85% 1RM (2-11).

The metabolic and hormonal signals initiated during ET turn on certain signaling proteins in skeletal muscle that lead to the aforementioned adaptations. ET involves repeated muscle contractions, which repeatedly releases calcium following each muscular contraction. This calcium activates the calcium-calmodulin kinase (CaMK) family of proteins, which is CaMKII in skeletal muscle (24). Active CaMK can increase the capacity for glucose uptake through the upregulation of the glucose transporter GLUT4, as well as increase mitochondrial volume by transcriptional upregulation of peroxisome proliferator-activated receptor-y coactivator 1a (PGC-1a), which serves as the mitochondrial biogensis regulator (25). With high-intensity endurance exercise there is a decrease of ATP and glycogen, which consequently increases ADP and AMP concentrations. This activates AMPK- activated protein kinase (AMPK), which facilitates an increase in fat oxidation during exercise, while also playing a role in the long-term regulation of mitochondrial volume (19).

In addition, the decrease in glycogen activates the 38 kDa mitogen-activated protein kinase (p38), which can increase the activity of PGC-1a (26-27). Through the rise of lactate and NAD+, there is the activation of the NAD+ dependent deacetylase family of sirtuins (SIRT) (26-27). Members of the SIRT family control the metabolic influx through the tricarboxylic acid (TCA) cycle, insulin sensitivity, and PGC-1a activity (26-27). There is speculation that one or more of these metabolic signaling pathways inhibit mTorc activation and limit hypertrophy when concurrently training, however there is more research needed (19).

There are certain mechanisms by which lactate removal, and ultimately the lactate concentration at a given exercise intensity, could be improved in endurance athletes through a RT program, however it is by no means fully conclusive. Hoff et al (1999) demonstrated improved short-term performance and improved work efficiency in cross-country skiers after a concurrent RT/ET program. Hoff and her colleagues observed a training-induced increase in RFD, which would allow for a shorter propulsion phase for a given overall power (9). This shorter propulsion phase would facilitate an extended muscle relaxation phase, which would reduce the time of contraction-induced muscle occlusion, and hence increase the time of muscle perfusion given the prolonged relaxation phase. This increase time for muscle perfusion would increase the mean capillary transit time (MCTT), which could ultimately allow for an increased MCTT every stride/revolution of an endurance event (9).

Hoff and her colleagues have suggested that due to the relatively large size of free fatty acids (FFA), the increased MCTT could enable an increased diffusion of FFAs into the muscle cells (9). This increased diffusion of FFAs could be described as glycogen sparing, which has been suggested to delay muscle fatigue through a reduced production of lactate (2). Furthermore, an increased MCTT could lead to an enhanced removal of metabolites produced by the contracting skeletal muscle, which could potentially delay fatigue and improve efficiency of the contracting muscle.


Practical Recommendations

  1. Use ET wisely, and strategically program it into your RT blocks. Intersperse HIIT and low-to-moderate intensity ET to keep ET volume at a minimum, while reaping the benefits of ET.
  2. Use low-to-moderate intensity ET (40-60% HRR) as a therapeutic tool to enhance recovery and improve mood state.
  3. Perform ET on a cycle or rower when available. This will reduce the exercise-induced muscle damage associated with running, which has a significant eccentric component. Cycling will also reduce the caloric expenditure since you are activating less musculature than with running, if you are struggling to maintain energy balance.
  4. Alternate between RT and ET “volume focused” weeks with ET frequency no greater than 3 days per week and duration no longer than 30 minutes.
  5. Any high-intensity ET should be performed early in the day, if engaging in RT and ET on the same day. After the morning ET, there should be a recovery period of at least 3 hours to allow AMPK and SIRT1 activity to return to baseline.
  6. RT should be performed in a fed-state, while being supported by a leucine-rich protein source immediately following RT. If performing RT and ET on the same day, it is suggested that a protein-rich source be consumed immediately before bedtime as well.
  7. If performing ET and RT on the same day, you must fully refuel between the morning high-intensity ET session and the afternoon RT session. This will ensure that muscle glycogen levels are restored, while not activating AMPK or SIRT1 activity.
  8. Low intensity, non-depleting ET can be performed before RT, which can provide an improvement in the ET response as well as improve the strength response during RT. However, the key is that the ET must be low intensity and non-depleting.
  9. Program your ET volume around your RT volume. In other words, if you are having a high volume RT week, you should lower your ET volume to compensate for that excess muscle damage and metabolic stress.
  10. Focus on maintaining energy balance! When concurrently training, you need to strive to replace the calories that you are burning. If you train in a caloric deficit, this will undoubtedly compromise your gains in muscular strength and hypertrophy.

Wrapping Up

CT can improve endurance performance through improving work efficiency and increasing anaerobic capacity. There is no literature indicating that CT is detrimental to any performance outcome associated with ET. In contrast, the literature indicates that there is a sharp dose-response relationship with ET frequency and duration (i.e. volume) on RT associated outcomes such as muscular strength, power, and hypertrophy. Therefore, strategically implementing ET based on the current scientific literature will assist in developing an optimal program for maximizing benefits associated with RT and ET, respectively. In addition, there are benefits from low, moderate, and high intensity ET that are maximized by performing ET at a variety of intensity levels. Therefore, interspersing low-to-moderate intensity ET with high intensity ET is crucial, as well as utilizing the current literature to program these strategically.

About the Author


Marc Lewis M.S.(c), CSCS, ACSM-CPT is a graduate teaching/research assistant in the Department of Exercise Science at the University of South Carolina and the Director of Sports Performance for Winston Salem Personal Training.

Twitter: @mtlewis14

Personal Training:



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How I Became A National Level Olympic Weightlifter In A Year


Biography: Erin Parker is the founder of Spitfire Athlete, a women’s strength training app that teaches you how to lift weights, and that stands for the pursuit of greatness & badassery. Spitfire Athlete is made by two female engineers who are also competitive weightlifters. Erin is a software engineer, Stanford graduate, and 48kg olympic weightlifter.

Download Spitfire Athlete:






I am a weightlifter. I say it with pride. You might not believe it when you see me, because I’m a 4’11” 105lbs woman, and my physique isn’t compatible with most people’s image of a weightlifter. But I am strong and have accomplished a number of physical feats, like lifting over twice my bodyweight, winning a 10,000 push-ups competition (it took me a year), and running multiple marathons.

I started lifting weights entirely for aesthetic reasons. I was phasing out my marathon training, wanted to learn how to squat, and was obsessed with sculpting a six pack, having toned legs, and huge glutes.

“Why didn’t anyone ever tell me this was so effective?” I thought. At the time, I was following Jen Rankin’s Muscle Building Program on Bodybuilding, eating a picture-perfect oatmeal, egg whites, chicken breast diet, and seeing fantastic results. I felt empowered to know that now I have the knowledge and discipline sculpt my body however I like, and I was happily training away at the gym for months.

July 2013: Me taking a progress picture selfie.


Along the way I discovered Bret Contreras and Kellie Davis’s Strong Curves Book. I wanted to improve my glutes and started incorporating hip thrusts and glute bridges religiously into my routine. And then something interesting happened. I was getting pretty good at heavy glute bridges. So, I got into a small competition with myself to lift more and more on the glute bridges.

I started glute bridging around 85lbs, and would add 5lbs each training day. I didn’t realize at the time that I was basically doing a linear progression, but in a few months, I found myself glute bridging a PR of 205lbs at 90lbs bodyweight, and I realized…I am strong. If I can lift over twice my bodyweight in this way, then I must be physically capable of lifting way more than I realize and doing more advanced exercises.

July 2013: My barbell glute bridge PR of 205lbs for reps!


Shortly thereafter, my gym started offering free personal training sessions members who haven’t previously purchased sessions, and I decided this was a great opportunity to learn the snatch and the clean and jerk, exercises which I viewed as advanced at the time, and which I was ready to incorporate into my routine. I didn’t realize that these exercises were part of the sport of olympic weightlifting. I just thought they looked cool. I also didn’t realize that this session would change my trajectory from casual fitness buff to seriously competitive athlete.

My trainer was Larry, a trainer who happened to be a competitive weightlifter and who was previously a competitive powerlifter.

“I see you around the gym a lot,” he said. “You seem to know what you’re doing. Can you tell me more about how I can help?”

“Can you teach me to clean and jerk and to snatch with a barbell?” I asked.

His eyes brightened up. “You want to learn the snatch and the clean and jerk? I can definitely teach the snatch and the clean and jerk. Ok, let’s go. Let’s see what you can do.”

Larry was very passionate about these lifts, and I was lucky to meet him, because he has been one of the most supportive people who would later encourage me to go after bigger goals and who I would see at many upcoming weightlifting competitions. He was the first person who saw and believed that I could be good in this sport.

My first clean and jerks and my first snatches weren’t pretty, but I got the gist of it, and best of all, they were incredibly fun! I felt like such a badass. At the end of the session he said, “Hey, there’s a weightlifting competition in 2 weeks. Want to do it?”

I didn’t even know weightlifting was a sport. I knew about powerlifting…but this was different. This was the snatch and the clean and jerk. Since they were the most badass feeling exercises I had ever done, I decided…I would do it. It couldn’t be harder than a marathon, right?

Two weeks flew by and I was ready as could be for my first competition. In a weightlifting competition, you have three attempts at the snatch and three attempts at the clean and jerk. Your best snatch and your best clean and jerk count towards your total. The lifter with the highest total in their weight class wins. You compete against weightlifters in your weight class, and for women, weight classes range from 48kg to 75kg+. I currently compete in the 48kg weight class.

The competition went really well, and I had a blast. Walk up to the platform and lift heavy shit? I’m all down for that and I would do it again. I even got more excited about the sport of weightlifting after doing some initial research and learning that elite weightlifters in my weight class are actually around my height.

For example, Wang Mingjuan, a badass 48kg Chinese weightlifter who won gold at the 2012 olympics is 4’11”. Hiromi Miyake is a 48kg Japanese weightlifter who won silver at the 2012 olympics and she is 4’9”. In weightlifting, you actually have an advantage if you are short and have shorter limb length proportions because you don’t have to carry the barbell as high to complete the lift.

Here is a chart from Bob Takano’s Weightlifting Programming book showing height ranges for female weightlifters as part of Leslie Musser’s Master Thesis, pulled from the competitors at the 2009 Pan American Weightlifting Championships.


When I noticed that in the 48kg class the minimum height was 4’6”, the maximum 5’0” and the mean 4’10”, it surprised me that my height was in this range! I had the misconception that all weightlifters were tall. This data gave me extra fuel and motivation to participate and compete. I no longer had this fear of being the only small person in the room. There is a weight class for me. I felt like I could belong.

October 2013: Me at my first weightlifting competition.


Here is a video of me at my very first weightlifting meet, hitting a PR of 45kg on the clean and jerk:

My first competition was a wonderful experience. I thoroughly enjoyed it and believed I could be good at it. I liked that my training consistently reinforced the feeling that I was strong and very physically capable.

Here is me at my second weightlifting competition, in January of 2014 (about 3 months later) hitting my then all-time snatch PR of 35kgs:

After testing the waters with a couple competitions, and on a beginner’s high, I decided to get serious and set an aggressive goal. After competing and beating personal bests, I could no longer be happy training the way I used to train. I was hungry. I wanted to be great at something, and I believed this was a sport where I actually have a shot at being great.

I joined a weightlifting team and started working with Coach Bram McArthur of SF Iron. He is both a weightlifting and a powerlifting coach who starts all of his athletes with a linear strength progression of squatting, deadlifting, benching, and overhead pressing. Upfront, I told him my goal was to qualify for a national level competition that year, either USA Nationals or the American Open. At the time, Nationals had a 109kg total to qualify and the Open had a 101kg total. My last meet total was 86kg at the time, so I would have to at least lift an additional 15kg, but I was sure that with hard work and consistency I could get there.

To see how well I was progressing relative to performance benchmarks, let’s look at this Weightlifter Classification System (developed in Eastern Europe), from Bob Takano’s Weightlifting Programming Book. There are six levels in ascending order, Class 3, Class 2, Class 1, Candidate for Master of Sport, Master of Sport, and International Master of Sport.


Here is my competition trajectory:

– First competition on October 2013: Sn 25kg, C&J 45kg, total 70kg (Class 3)

– Second competition on January 2014: Sn 35kg, C&J 51kg, total 86kg (Class 2)

– Third competition on March 2014: Sn 43kg, C&J 57kg, total 100kg (Class 1)

– Fourth competition on April 2014: Sn 44kg, C&J 60kg, total 104kg (Class 1) & Qualified for American Open

– Fifth competition on August 2014: Sn 40kg, C&J 55kg, total 95kg

– Sixth competition – American Open – on December 2014: Sn 44kg, C&J 53kg, total 97kg

Like all the athletes who train with Coach Bram, I started with my first linear strength progression, squatting, benching, overhead pressing, and deadlifting three days a week and increasing weights linearly each week. “We need to put some strength on you,” Bram would say…and yeah, he still says this!

After a few months, I couldn’t believe how much I was lifting. Relative to my bodyweight, it was a lot, although relative to competitive weightlifters, my strength numbers aren’t that impressive.

Today, I believe that we all should go through a linear progression at some point in our lives. Regardless of gender, regardless of whether you’re training for health, strength, endurance, or aesthetic reasons, I believe you should go through an LP, because it will make your body stronger, and you will perform better at everything. Of course, there are sports like gymnastics where the athletes don’t lift weights, so in those cases do what your coach says, but if you’re a recreational athlete, a basic LP done in your “off season” to build strength, can transform your body’s ability to move and perform. It’s also really eye opening to see how strong you are in a short period of time. Each training day, you’re lifting more than you ever have before, basically pushing your limits each time. You can literally feel yourself getting stronger.

My numbers when I started:

  • Squat 1RM 140lbs
  • Deadlift 1×5 140lbs

My numbers after my first LP:

  • Squat 1RM 190lbs (1.9x bodyweight)
  • Deadlift 1×5 210lbs (2.1x bodyweight)
  • Bench Press 1RM 90lbs
  • Overhead Press 1RM 80lbs

I had gained 10lbs of bodyweight, so I hit these numbers weighing around 100lbs. Since I was entered the sport weighing 90lbs, I needed to build up to my competition weight at 105lbs, which I had never ever weighed before. In the sport of weightlifting, you want to weigh as close to your weight class as possible, and since I was 15lbs under the lightest weight class, I needed to gain weight to be competitive.

My first linear progression was over, and sure enough, the gains came! Soon after I hit a snatch PR of 45kg. Moving up to the yellow 15kg plates on the snatch felt huge!

45kg Snatch PR:

I competed at the Hassle Free Open and made a competition total of 100kgs, up 14kgs from my last meet.

Here are my lifts from the Hassle Free Open:

43kg Snatch:

57kg Clean and Jerk:

I was 1kg short of qualifying for any national level meets, so I continued my training and a month later, I tried again. I was training 3-4 days per week and my training consisted mostly of snatches, clean and jerks, and squats.

At my next competition, I made a 104kg total, and qualified for the American Open! I graduated to being a “Class 1” lifter now!

Here are all my lifts from the CTS Wine Country Classic in April 2014, where I made a 104kg qualifying total:

I could have stopped there and just focused on the American Open, but being the aggressive, ambitious go-getter I am, I decided to try to qualify for nationals. I was only 5kgs away from the qualifying total. USA Weightlifting even sent me this really nice email to encourage me to go for it, which I appreciated, even though it’s likely automated. :)


So what was next? I had finished my first LP, transferred those gains to my olympic lifts, and added 14kg to my total. I almost made my last snatch and my last clean and jerk (which would have given me the total needed for nationals) but missed by a very close margin.

For my next competition, I needed to continue practicing the olympic lifts with heavy weights, but I also needed to continue making strength gains. So my coach progressed me to an intermediate program, the Texas Method for weightlifters. This type of program is appropriate for an intermediate strength athlete and relative beginner in weightlifting. The focus is to keep driving the strength of the lifter while sufficiently practicing the olympic lifts.

My program looked like this:


Goal: Practice the olympic lifts.

Sn 2×4-8

C&J 1×5-10


Goal: Volume strength work, to drive strength up.

Sq 75% 5×5

Press 75% 5×5

Chins 3×5-8


Goal: Check progress on lifts and overall recovery.

Sn max for day

C&J max for day

F Sq 3×3


Goal: Check progress on strength and overall recovery.

Squat 1×5

Press 1×5

DL 5×1

The volume day was by far the most challenging. I had to do 8 sets of 2 snatches at 90%+ range followed by 15 clean and jerk singles also in the 90%+ range, with a maximum of 1-2 minute rests in between each set.

Here is a video of me doing (aka struggling) through the Texas Method program:

At first I thought, “This is freaking insane! Is it physically possible to make so many lifts at 90%+?” Not only that, I had to increase the weight with each lift, even if I only increased it by half a pound. Practice was long and difficult. I would barely have a chance to catch my breath, I would be dripping sweat, feeling like I barely had it in me to continue…and then I would have to push myself even harder and lift even heavier than my last rep.

My first week, I would miss lifts left and right. When I was “failing all the time” I felt like I didn’t know what I was doing. But I kept on and gave it my all, even if it felt sloppy. Then…something kind of magical happened. After about a week or two of training at this level, my body adapted. And so did my mind. I suddenly started making these snatch double at 90% of my capacity. I also no longer got so tired, mentally, and was able to stay focused through the entire 8 sets of 2. My technique also started improving, probably because of all the practice, and it was an amazing feeling because I started actually making heavy snatches more consistently.

July 18, 2014, A video of me making heavy snatches more consistently:

On my heavy strength days, I found myself squatting 180lbs for doubles…like it’s a totally normal thing. I remember sharing a squat rack with a guy when I was at a commercial gym once. I had to do something like 185lbs for a double. He was squatting around 135lbs, and when I started warming up into the 150s, 160s, he started trying to squat way outside of his comfort zone just to try and keep up with me. Why? I have no idea. And then he started really struggling at 165lbs. When I finally did my last warm-up at 175lbs and my work set at 185lbs he said, “Oh my god. I can’t even keep up with you.” He was flabbergasted. I laughed and thought to myself, “Of course you can’t!” 😉

I competed in the Tommy Kono Open that summer. It was my worst competition ever for two reasons: 1) I had to cut weight for the first time and 2) I was a complete nervous wreck. I was very care free with my diet in the months before, using my hard training as an excuse to go all out, and now I was well over my weight class. Darn.

Cutting for the first time was tough because I felt extremely energy-deprived and like there was nothing in my muscles. On top of that, I was a nervous wreck because in my mind, this meet was a really important competition and I didn’t want to fuck it up. I wanted to qualify for nationals. This was my last chance! But I was so nervous that I was basically hyperventilating in the warm-up room and I felt like my heart was going to explode out of my chest. In my mind, I kept worrying, “Oh my god what if I fail my opener? What if I don’t make the total? All my hard work will be wasted!”

I even missed my 35kg warm-up snatch. My coach immediately knew something (more like, a lot of things) were really off. Because of the cut and my mindset at the time, the bar felt really heavy, when it shouldn’t have. I only made my opening snatch and my opening clean and jerk. Even though I ended up medaling at the meet, I didn’t make the total I had wanted, and felt like a failure.

Here is what I learned: First, I want to resume having a great diet and stay close to my weight class, not go over too much, and avoid drastic weight cuts. Second, I want to get my mental game together. I want to learn how to not be panicking on the day of competition, and to stay calm, composed, and ready to perform.

A lot of things happened in the next five months after this meet and before the American Open. My start-up, Spitfire Athlete, received investor funding from one of the top accelerators in the country and my co-founder and I flew over to Boston for three months to aggressively grow and build the company.

We had an aggressive schedule, where I had meetings all morning and would code all night, and work with my co-founder towards shipping an app update every week. We didn’t even lift for the first couple of weeks of the program, because things were so crazy and we were barely sleeping.

When our schedule calmed down just a little bit, we managed to get some time to lift at the MIT gym, basically the only affordable gym in the area that we could reach via public transport that had a platform, olympic bars, and bumper plates. But I really struggled. After not lifting for a few weeks, my technique was all over the place, knees caving in, pressing out, and I felt so weak. I completely deprioritized my health, nutrition, sleep, and weight training in order to hit aggressive goals. I remember lifting on days where we only had 6 hours of sleep and where I struggled to make a 40kg snatch.

I reasoned that “this was only going to be for three months, I’ll gain everything back when I’m back in San Francisco” but I didn’t realize it would take months to gain back strength that I had lost in a few weeks. If I were to do it again, I would take the more long term approach and better balance my training with more focused company milestones (because really, we didn’t have to do it all, we just really wanted to).

Nov 2014: Me and my co-founder in Boston, celebrating Spitfire Athlete’s 1 year anniversary. Two women on a mission to make strength training a part of every woman’s routine.


As Techstars came to an end, we had achieved some very meaningful goals, like our 50,000+ users worldwide, hitting our engagement goals (did you know that most workouts tracked on our app are over an hour long?) and ranking in the top 10 for App Store search results like “women’s fitness” and “women’s strength”. We had the most fun pitching to a theatre full of investors and ending our presentation with a clean and jerk. When we talk about badassery, we mean it.



It was close to the end of November 2014. I was back in San Francisco, and training at my coach’s shiny new gym, SF Iron. Squat racks, platforms, and barbells for all! The American Open was in less than one month! My coach advised me to start visualizing having successful lifts. He recommended visualizing me getting nervous, and then controlling my nerves and then executing the lifts well. I did some additional research on the subject of athletic performance visualization and found a book called 10 Minute Mental Toughness.

I read it and decided to give it a try. I would meditate every day, either first thing in the morning or right before practice.

In the first part of the meditation, I would start by taking a deep centering breath. Then, I repeat my performance statements to myself. Here is part of my performance statement: “I have what it takes. Today, I am going to give it my all. I am going to give it every single fiber of my being. I am going to finish strong.”

I would repeat this to myself until I started believing it. And then I would imagine myself at the American Open and getting ready to make my opening snatch. I would imagine feeling nervous, seeing the loaded barbell on the platform, and then imagining myself taking a deep breath, clutching the barbell in my hook grip, and then in slow mo, making the lift. I would imagine myself smiling and the audience cheering at the end of the lift. I do this three times for the snatch, three times for the clean and jerk, imagining myself making the lifts, no matter what. I would imagine myself pushing through and finishing strong on the jerk.

I finished by reciting my entire performance statement again, and then taking a few deep breaths, and then I was out.

I did this meditation every day in the weeks leading up to the competition. I started noticing that it also had an immediate effect on my confidence in practice. Within the first week of doing this, I already started making more of my heavy lifts, particularly my heavy snatches which is what I was the most afraid of.

Now that I was actually visualizing making these snatches more than I was visualizing failing these snatches, I actually started making them! It was quite eye opening, actually, to realize that in the past I was actually visualizing failure more than I was visualizing success.

Before I knew it, I was on a plane and flying off to Washington DC for the American Open, my first national level competition! Since I had recently gotten back from Boston, my strength numbers felt nowhere near where they were earlier in the year, so my focus for this competition was to give it my best mental game and to make my openers. Anything after my openers was icing on the cake.


On the day of the meet, I was up at 6:45am, ready to weigh in by 7am. Yes, I was very nervous. But I think the meditation practice really did pay off, because I wasn’t a complete nervous wreck, and my focus was on making my lifts, and nothing else. Mentally, I was unshaken. Yes, I could still feel my heart beating hard, and my breathing was a little fast, but I kept a focused look on my face and I knew I was going to make it through without panicking.

I made my opening snatch – easy. It felt GREAT. It felt light. I felt strong. Then, I made a 44kg snatch and it also felt solid. I could even hear my mom and my grandma cheering me on from the audience. This was their first time ever seeing me lift!

After my snatches were over, I felt a huge sense of relief. I had gotten over the scariest part of the meet! I thought, “Wow. I was able to get control over my nerves and perform when it mattered.”

Although I finished all my 3 clean and jerks, the judges only counted the first one. My last two were disqualified for press-out, unfortunately. However, it was, by far, my best performance ever, because my mind was in the right place. I felt fantastic. I was cool, composed, and when I did my lifts, I felt confident.

One of my favorite parts of going to this meet was getting photographed by Hookgrip. I had dreamt of getting photographed by Hookgrip one day, and here it was!



I’m excited to continue onward with this journey and to push myself year by year. I love this sport and can’t describe how much fun I have.

As I write this, since the American Open, I have achieved new PRs, namely, a 50kg snatch (hell yeah for the beyond bodyweight snatch), a 63kg clean and jerk, and 78kg front squat. If you go back to the chart from earlier, this in-practice total would allow me to graduate from “Class 1″ and make it to “Candidate for Master of Sport”. Now I just got to take this performance to my next competition.

What’s next? Well, this year, I’m going to try to qualify for Nationals and the American Open again, although this time the qualifying totals have increased to 133kg and 123kg, respectively, so I’ve got to keep on training, working hard, giving it my all.

I feel stronger than ever. If you’re thinking about competing in the sport of weightlifting, I say go for it! Give it a try. You’ll never know, you just might fall in love with feeling like badass every day and never go back.

I’ll end this with one of my favorite quotes by Mia Hamm: “Somewhere behind the athlete you’ve become and the hours of practice and the coaches who have pushed you is a little girl who fell in love with the game and never looked back… play for her.”


Cardio & Appetite: Does Cardio Make You Fat?

Cardio & Appetite: Does Cardio Make You Fat?
By Fredrik Tonstad Vårvik

Does endurance-training (cardio) increase or decrease your appetite? What about resistance training?

Some might say that exercise increases appetite, while others say the opposite. The plain truth is that since exercise burns calories, you should think appetite increases to make up for those burned calories. For those who want to lose weight, that might come as a shock. What sounds logical is not always true. The media have done a great job of convincing the public that exercise increases your appetite and that you end up eating more and getting fat.

I have read and looked into the latest reviews and meta-analysis, which should sum up nicely what we know to date. The research that has been done is mostly short-term. The authors of the studies admit some limitations of the studies – mainly sub-optimal study design and small sample sizes.


Short term

A meta-analysis by Schubert et al, 2013, looked at acute energy intake up to a maximum of 24 hours post-exercise (1). Twenty-nine studies, consisting of 51 trials were included. Exercise duration ranged from 30 – 120 min at intensities of 36-81% VO2max. Test meals were offered 0-2 hours post-exercise. If subsequent meals were presented, they were 4-5 hours apart, from 1-4 meals. The overall results suggest that exercise is effective in producing a short-term energy deficit. Meaning that the subjects did not compensate for the energy they expended during exercise, in the 2-14 hours after exercise. Forty-five studies reported relative energy intake after exercise. They showed that participants compensated for the energy used in exercise by around 14%. All trials reported absolute energy intake. Despite large energy expenditures, the absolute energy intake was only slight higher in the exercise group compared to the no-exercise group, with a mean increase of about 50kcal.

These results are in line with a review of Deighton et al 2014 (2). Namely, that an acute bout of exercise does not stimulate any compensatory increases in appetite and energy intake on the day of exercise.

Short and long term

A review by Donnelly et al 2014, included 103 studies in their review (3). The study design included cross-sectional- , acute/short-term- , non-randomized- and randomized-studies. Exercise duration ranged from a single 30-min exercise bout to daily exercise over 14 days. Energy intake was measured from once post-exercise up to 72 weeks. Overall, the energy intake was reduced in participants doing exercise compared with participants not doing exercise. As noted by the authors: “our results from both acute and short-term trials suggest that any observed increase in post-exercise energy intake only partially compensates for the energy expended during exercise. Thus, in the short-term, exercise results in a negative energy balance.”

As for long term, only 2 out of the 36 non-randomized and randomized trials, in duration from 3 to 72 weeks, reported an increase in absolute energy intake in response to exercise. Moreover, 30 of the studies reported no change in calorie intake, while five of the randomized studied reported significant decreases of 200-500 calories per day in response to training.

Blundell et al, 2015, agrees that exercise has little effect on energy intake within a single day (4). However, in the long-term, there seems to be a raise in compensatory energy intake, ranging from 0 % to 60 % compensation in energy intake for the exercise expenditure.

Low, medium & high fitness level

The meta-analysis by Schubert et al, 2013, indicated that individuals of low and moderate fitness reduce energy intake more than those with high fitness level (1). They reference previous work that agrees that individual who are more physically active more accurately regulate their energy expenditure. The researchers write that active individuals compensate for about 23% of energy expended while inactive individuals actually had a negative compensation of -35,5%. In Donnelly et al’s review, they found no difference in fitness level and energy intake (3).

Resistance training:

Five interventions in Schubert et al’s meta-analysis utilized resistance training (1). The sessions were between 35-90min with 10-12 repetition maximum and 2-4 sets. Acute energy intake up to 14 hours were reduced compared to energy expenditure; however, it was not as reduced as the groups with endurance training. Worth noting is that energy expenditure of resistance training is difficult to quantify precisely. So don’t stop doing resistance training, there are a lot of other positive advantages, like improved body composition. In addition, the review by Donnelly et al found no difference between energy intake post-exercise in endurance exercise and resistance training (3).

Intensity & duration

An effect of exercise intensity was not found in Schubert et at’s meta-analysis (1). However, the researchers mention in the text that others have found that intensities above 70% VO2max appears to reduce appetite but with minor changes in absolute energy intake. In contrast to this finding, Donnelly’s review found no significant difference in exercise intensity and duration on energy intake (3). Deighton et al also concludes that high-intensity does not reduce appetite more than low-intensity (2). However, if you look more into the studies analyzed in Donnelly’s review you will see that high-intensity might have some advantages concerning reducing energy intake.

Compensators & responders

The mean (average) in Schubert et al’s meta-analysis showed a short-term reduction in energy intake (1). However, some actually increased their absolute energy intake post-exercise. Some of the trials in Donnelly et al’s review also increased their energy intake, meaning that some compensate more after the energy deficit the exercise gives (3). Compensators have showed an increase in hedonic response to food, which means they are more sensitive and “weak” to food that give more pleasure eating.

How does exercise influence appetite?

As stated in the start of this article – since you burn calories through exercise you should expect to increase appetite and make up for it with eating more. As the research says, in most people it does not.

The reason might be because exercise suppresses ghrelin levels (a hormone that stimulates energy intake), while increasing hormones that increase satiety, such as peptide YY (PYY) and glucagon-like-peptide 1 (GLP-1) (1). This is in line with data from Blundell et al, 2015, which means that increased physical activity improves satiety signaling and appetite control. And that this system gets deregulated in sedentary people, thereby permitting overconsumption, as shown in the illustration (4).


Exercise does also make adjustments other than with gastrointestinal hormone response and gastric emptying: blood flow, muscle cellular metabolism, adipose tissue biochemistry as well as brain activity gets adjusted by exercise.

Why do individuals lose less weight than would be expected during long-term exercise interventions?

Several theories exist regarding why individuals do not lose as much weight as expected during an exercise program (1).

  • Some might change their dietary intake in response to exercise, especially the compensators
  • Some prefer sweet and high-fat food post-exercise
  • Energy intake may not increase per se, but rather a compensation of physical activity outside the exercise program decreases
  • The research mentioned in this article, stated that there is a highly individual difference between how much you compensate with energy intake, if you compensate much you will see little difference in weight

The bottom line is, on average, exercise will not make you eat more. Moreover, exercise is a tool you can use for losing weight. Energy expenditure of exercise is the strongest predictor of fat loss during an exercise program, according to Deighton et al (2).

Author bio

Fredrik Tonstad Vårvik is a personal trainer & nutritionist. He writes articles and work with online coaching at fredfitology. Follow him and his colleagues at facebook & twitter. Check out FredFitology for more info.



  1. Schubert MM, Desbrow B, Sabapathy S, Leveritt M. Acute exercise and subsequent energy intake. A meta-analysis. Appetite. 2013 Apr;63:92–104. LINK
  2. Deighton K, Stensel DJ. Creating an acute energy deficit without stimulating compensatory increases in appetite: is there an optimal exercise protocol? Proc Nutr Soc. 2014;73(02):352–8. LINK
  3. Donnelly JE, Herrmann SD, Lambourne K, Szabo AN, Honas JJ, Washburn RA. Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? A systematic review. PloS One. 2014;9(1):e83498. LINK
  4. Blundell JE, Gibbons C, Caudwell P, Finlayson G, Hopkins M. Appetite control and energy balance: impact of exercise. Obes Rev Off J Int Assoc Study Obes. 2015 Feb;16 Suppl 1:67–76. LINK


Muscles Cannot Change Size Without Changing Shape

Let me lay down the groundwork for this guest article from Andrew Vigotsky. On March 3rd, I posted THIS thread on Facebook. It’s a before/after pic of Casey Bergh, which I used to illustrate my point that muscles can indeed change shape. Many fitness professionals chimed in, stating that muscles don’t change shape, they just grow. Before I entered the S&C scene, I was a high school Algebra and Geometry teacher, so I know my mathematics. I kept stating repeatedly throughout the thread that muscles don’t just grow proportionately larger, and that since the fixed endpoints don’t grow as much as the muscle belly, the shape must necessarily change. In addition, some regions grow more than other regions depending on which portion of the muscle is most highly activated, but that’s not as important.

My colleague Andrew and I were discussing this one night, and in typical fashion, he sent me this guest article a few hours later. Andrew is the smartest kid I’ve ever known, and when his mind is fixed on something, he gets to the bottom of it very quickly. You might be thinking, “who gives a shit?,” in which case we wouldn’t blame you. But this is the sort of thing that biomechanics geeks love to contemplate. We’re not saying that resistance training turns triangles into rectangles, we’re simply stating that muscles cannot grow without changing shape. Hopefully at least a few of you geeky meatheads will appreciate the article. 

Muscles Cannot Change Size Without Changing Shape
By Andrew Vigotsky

Last week, Bret posted a rant on Facebook describing how muscles can change shape. Many say this is impossible, but to be frank, they’re wrong. The purpose of this piece is to show, mathematically, that a muscle cannot change size without changing shape.

Firstly, it is important that we understand how shapes are comparable. Shapes can be compared in three ways.

  1. Congruency – congruent shapes can be made identical and superimposable by translating, rotating, or reflecting.
  2. Similarity – similar shapes can be made identical and superimposable by translating, rotating, reflecting, or proportional
  3. Isotopy – isotopic shapes can be made identical and superimposable by deforming a shape in such a way that does not “break” it (think tying a knot).

When it comes to muscle, the most appropriate measure of comparing its shape is similarity, as it changes size, so scaling may be necessary.

In order to do this, we will assume muscle has a hyperbolic cosine (my favorite function) shape, which does have a strong correlation with a muscle’s actual architecture. Next, we know points of muscle attachment cannot change, so let’s say the muscle before and following hypertrophy is modeled by the following function, where x is a position and α is the coefficient of hypertrophy.

1Graphically, it looks like this. Of course, these numbers are arbitrary, but the principles of this model still hold true.


Let’s say the muscle doubles in size, α = 2.


Traditionally, shapes are compared using Procrustes analysis, which is when the shapes are optimally scaled, rotated, and superimposed to best match. Then, Procrustes distance is calculated by

4Of course, this is an approximation, as, in reality, there are an infinite number of points that can be analyzed. Nevertheless, I used MATLAB to find the Procrustes distance between these two functions. If a distance exists (d > 0), then these functions are dissimilar.

Using 4585 points, a distance of .0070 was found. Using 5 points, a distance of .0074 was found. These functions are not similar; therefore, these shapes are different.

A muscle cannot change size without changing shape, as the attachments of a muscle remain constant, but the size of the muscle changes. In order for a muscle to remain the same shape, the attachments would need to shift with changes in size. Lastly, this model assumes uniform growth, but in reality, this does not occur, and non-uniform growth would make d even larger (more dissimilarity).