Tyler Robbins Fitness

B.Sc. Biochemistry, Certified Strength and Conditioning Specialist (CSCS), Certified CrossFit Trainer (CCFT/CF-L3), USA Weightlifting Level 1

Day 111 - Nutrient Timing for Resistance Exercise Part 1

I came across an absolutely amazing article in the Strength and Conditioning Journal titled, "Nutrient Timing for Resistance Exercise" written by a team of PhD and CSCS certified individuals. This is probably the single-greatest resource I have come across detailing what is referred to as "nutritional timing" when it comes to resistance training, so if you are interested, pick up a copy for yourself!

I am not going to copy the entire article obviously, but over the next few blogs, I am going to include a few snippets and details from the article here on my blog to not only inform all of you, but to also try and convince you to pick up a copy of the article for yourself (if possible).

Part 1: Enhancing Performance in Individual Resistance Exercise Training Bouts


During resistance training, our muscles use and expend muscle glycogen. That is the primary fuel source for strength training. I have personally seen many debates regarding whether or not to supplement prior to a resistance training session with carbohydrates to enhance performance. Here is what the article has to say:

Despite this depletion of skeletal muscle glycogen, the majority of studies in which supplemental carbohydrate was ingested before a resistance training bout did not report improvements in resistance training performance. In the limited studies that reported a performance-enhancing effect of pre-exercise carbohydrate supplementation, it should be noted that the resistance training workouts were not of a practical nature and did not resemble workouts that are conducted in a typical athletic strength and conditioning program.

It should be noted that certain individuals feel the need to consume something prior to a resistance workout in order to avoid "bonking". For most individuals (such as myself), training on an empty stomach (early morning for example) should not be a problem as your muscles and liver store plenty of glycogen to sustain energy levels for a resistance training session.

On the other hand, if you believe that you "hit a wall" towards the end of your workout, you may want to either try consuming a small amount of carbs prior to a workout, or consume proper amounts of nutrition following a workout. It is the post-workout nutrition that allows you to sustain energy levels for following bouts of exercise.

Protein/Amino Acids

This is also a common debate amongst fitness enthusiasts. Many believe that supplementation of branch-chain amino acids (BCAAs) prior to exercise will enhance performance during a training session. Turns out, however, that only 3 of the approximately 20 amino acids are oxidized for energy (leucine, isoleucine, and valine), and going beyond that, they are oxidized for energy at levels below carbohydrates and fats.

The authors reported that the BCAAs had no effect on resistance exercise performance. Because of their limited role in oxidation during exercise and their inability to improve acute resistance exercise performance, amino acids should not be ingested before a resistance exercise bout, with the belief that they will improve the performance of the subsequent workout.

Keep in mind that the authors of this article clearly state that pre-workout consumption of BCAAs should not be used with the belief that they will improve performance, however there may be some validity to ingesting protein prior to a training session to reduce/reverse the catabolic effect.

Carbohydrate and Protein Supplementation

Similar to ingesting either carbohydrates alone, or protein alone prior to a workout, a concoction including carbohydrates and protein together yield no measurable benefits on performance.

In summary, it appears that ingesting carbohydrate alone, protein/amino acids alone, or carbohydrate plus protein before resistance exercise does not improve the performance of the resistance exercise workout in terms of total amount of weight lifted during the workout. In contrast, there are favorable outcomes resulting from carbohydrate and protein supplementation in terms of enhancing adaptations over time and on recovery.

Today's blog covered a good portion of pre-workout nutritional timing, Sunday's blog will then be targeting post-workout nutritional timing.

Quote of the day:
"Defeat is not the worst of failures. Not to have tried is the true failure."
~ George Edward Woodberry