Posted on


MUSCLE HYPERTROPHY: The What and Why for Baseball Performance

No matter what sport, every athlete wants to get bigger, faster, and stronger to excel on the field. We can talk the talk, but can we walk the walk?

We don’t just lift weights to look cool. There is a method to the madness. Hopefully after reading this article, you’ll understand how you can put some lean tissue on your body and some of the sciences behind it.

With any dynamic movement, there are two main muscle actions: concentric and eccentric.

A concentric muscle action is when the muscle shortens, and an eccentric muscle action is when the muscle lengthens.

Take a squat for example. On the descent, the muscles of the quadriceps and glutes eccentrically lengthen to absorb force. On the way up in the squat, the same muscle groups must then concentrically shorten to produce force into the ground.

The word “hypertrophy” itself means growth. Muscle hypertrophy is the growth of muscle tissue.

This article is mostly target for the baseball players who can increase muscle size and thickness throughout a training cycle. Although, younger players can benefit from this article as well.

So…how can you get your lean tissue to grow? Let’s dive into the science.

Training Age and Biological Age

How long you’ve been resistance training (training age) is a huge factor on your ability to adapt to resistive stimuli.

For example, let’s compare the beginner 14-year-old athlete and the intermediate 17-year-old athlete. Both having a different biological age and training age, these individuals will adapt to a stimulus different from one another.

The 14-year-old athlete has never touched a weight in his life. When executed properly, resistive exercises will basically teach his muscles how to contract efficiently while performing these foundational exercises.

Although there may be no apparent physical changes, most (if not all) of the adaptation will be within the nervous system. Depending on puberty, this athlete will not increase muscle size and thickness due to hormonal levels. However, there is no doubt that this athlete will be a lot stronger when performing an individualized program.

The 17-year-old athlete has some lifting experience, and his hormone levels will give him a greater chance to increase muscle size and thickness as well as nerve conduction to the muscle cells.

The current theory is that heavy lifting (1-6 repetitions) will recruit high-threshold motor units within the muscle cells to promote maximal muscular contractions.

Bigger muscles have an increased amount of contractile proteins, which is positively correlated with muscle strength. Therefore, high load AND low load training within the same training cycle is important for increased muscle size and strength [1].

For the baseball athlete, it may not be optimal to always perform any resistance training at high loads all the time due to the speed of the movement. A HEAVY lift is at a slow speed, when any baseball action requires QUICK movements!

Screen Shot 2017-08-02 at 6.48.30 PM

Trained individuals have a lower adaptive ability to resistance training. This is why understanding the multiple factors that we can manipulate in a program can propel you to future gains!

Metabolic Damage/Cellular Swelling Response

We can manipulate hypertrophic responses to resistive stimuli with the use of a few variables: training volume, rest period length, exercise selection, and time under tension.

The cellular swelling response that we see from resistance training comes from high training volumes (3-6 sets, 8-15 repetitions) and generally low rest period lengths (30-90 seconds).

Since the training room is a controlled environment, strength coaches can keep track of training volume and intensity in programs. The easiest way to add a metabolic damage/cell swelling response to your training regimen is with increasing the amount of sets and repetitions of exercises. This should be done after your heavy lifting.

We can also increase the amount of cellular swelling with time under tension of an exercise. Performing a complex exercise under a slow tempo increases the amount of muscular effort and work.

Performing an exercise with an eccentric focus has shown to increase regional-specific muscle hypertrophy [2]. Having an eccentric focus on an exercise aids in increasing time under tension.

Your off-season training program should transition from high volume of lifting (sets and repetitions) to a lower volume of lifting. This is because the metabolic damage response to training will result in your muscle feeling achy and sore with a high number of metabolites and by-products within surrounding tissues.

Mechanical Damage Response

Resistance training stimulates muscle protein synthesis to remodel muscle tissue. For a positive adaptation to occur, there must be a positive balance between synthesis (build up) and degradation (breakdown).

Research has shown that performing resistive exercise at moderately high intensities near muscular failure result in greater muscle activity when compared to low intensities, and eccentric-focused exercise can elicit a greater hypertrophic response [1,2].

Exercises done at a high intensity should be performed at the beginning of your workout once your speed work has been completed (sprinting, jumping, high velocity lifts, etc.).

Multiple short-term studies showed that using an emphasis on eccentric muscle action results in a more rapid protein synthesis response and release of anabolic (tissue-building) hormones [2].

If you want to add some eccentric-focused work (3-5 seconds) into your training, your best bet is to add it in the off season when you’re trying to add more training volume to get your tissues to grow! [3].


Although we can argue and say that high load training is superior to low load training regarding increases in muscle strength and size, the literature supports to the use of high load AND low load training to promote muscle growth.

I think the most important variable when considering increasing muscle strength and size is relative intensity. Having intent during exercise execution is critical for muscle growth!

Using both high and low loads within the same session will give you the biggest bang for your buck. Training to failure towards the end of a training session can also be used to chase hypertrophic responses [3].

Understanding where you are at regarding your training age is the first step in the training process. Once you’ve figured that out, it’s time to manipulate some training variables so you can break a plateau and see some increase in muscle size!

The reason why we should strive to increase our lean tissue mass in the off season is to understand that bigger muscles have more contractile proteins, which give your muscles a greater chance to consume heavier loads.

The NEXT step in attaining some lean mass is using these contractile proteins at a HIGHER velocity! MASS EQUALS GAS, pitchers!

If you want to learn even MORE about how you can optimize your off-season tissue gains, click the link!

Continue to grow,


Jarad Vollkommer, CSCS

Assistant Director of Performance

Infiniti Sports Performance


  1. Gonzalez, A.M. (2016). Acute anabolic response and muscular adaptation after hypertrophic-style and strength-style resistance exercise. Journal of Strength and Conditioning Research 30(10), 2959-2964.
  2. Schoenfeld, B.J., Ogborn, D.I., Vigotsky, A.D., Franchi, M.V., and Krieger, J.W. (2017). Hypertophic effects of concentric vs. eccentric muscle actions: A systematic review and meta-analysis. Journal of Strength and Conditioning Research 31(9), 2599-2608.
  3. Schoenfeld, B.J. (2010). The mechanisms of muscle hypertrophy and their application to resistance training. Journal of Strength and Conditioning Research 24(10), 2857-2872.

One Reply to “Mass Equals Gas: Getting Bigger in the Off-Season”

Leave a Reply