When we think about building muscle and getting fit-it seems cut-and-dry. You perform a weight bearing exercise, it tears muscle fibers, it heals, you build muscle. Basically, that is true. But it goes deeper than that! There is so much more involved in the entire process. In this article I will touch on the neuroendocrine response as it pertains to exercise.
Neuroendocrine is the vital communications between the endocrine system and the nervous system. Hypertrophy and increased strength rely upon the neuroendocrine reworkings and responses produced during resistance training.
During the exercise process the neuroendocrine response releases vital hormones are into the blood stream. These hormones are key in muscle repair and building. These hormones include testosterone, growth hormone, cortisol, insulin-like growth factors (IGF-1), and catecholamines. When we put stress on our muscles (exercise) they begin to breakdown; this is called catabolism. This sounds detrimental but it is actually a positive first step towards bigger muscles and increased strength. The hormones produced and released through the neuroendocrine response begin to assist in the rebuilding of the damaged muscles. This is called anabolism. The actual growth or increase in size of the muscle is done during recovery.
Specific exercises and exercise cycles can maximize the neuroendocrine response. Working large muscle groups first in a workout will release vital hormones early in the workout that will benefit you throughout the remainder of the day. Kraemer et al. found that “Large muscle-mass exercises such as the Olympic lifts, deadlifts and jump squats have been shown to produce large elevations in testosterone in comparison with small muscle-mass exercises” (2005).
The intensity, set range, rep range and volume of the exercise also has an effect on the neuroendocrine response. The increase in any of these criteria will release the important hormones needed to assist in building muscle and increase strength.
In conclusion, in order to carve out the muscular physique you’ve always wanted, you need to maximize neuroendocrine response. In order to do this you must focus on working large muscle groups first in the cycle, leaving the smaller muscle groups for last. Also, use higher volume and moderate to high intensity with shorter rest intervals between sets. Keep your muscles guessing. Challenge your muscle to outperform even your own expectations and you will see them grow.
Kraemer W.J., Ratamess N.A. Hormonal Responses and Adaptations to Resistance Exercise and Training. Sports Medicine 2005;35(4)