Along with the overload principle, there is a scientific training principle that is complementary and very effective. It is called the Antagonistic Multi-Set Training Principle. Antagonistic muscles are muscles, or groups of muscles, whose contractions provide for movement in opposing directions.

Before getting into the application of this principle, let’s first take a moment to familiarize ourselves with the reasoning behind using this principle. There are a few processes at play that affect muscular contractions (see my previous post about “Contractile Failure and Lactic Acid). What it boils down to is extended rest, nervous relaxation, and lactic acid removal.

Extended Rest & Lactic Acid Removal

Removal of lactic acid from the muscle tissue cells between sets is the most effective method of ensuring that a minimal number of repetitions are los in following sets. Extending between set recovery periods is the most effective method in accomplishing this goal.

The cori cycle is a metabolic process that ultimately converts lactic acid that has been released into the blood back into energy by the liver. This energy can then be used by the working muscles. This does not change the fact that lactic acid inhibits contractions upon its production within the cell.

Training antagonistic muscle tissue back-to-back in the same workout offers one solution to this problem of optimizing lactic acid removal. Suppose you need 3 minutes between sets to allow for the performance of the same number of reps in the following set. What would happen if, after completing a set and waiting those 3 minutes, you went to a different movement for a totally different antagonistic muscle group? After completing this set, you waiting another 3 min, and once again returned to the original movement. The workout would last the same amount of time, only each muscle group would spend twice the amount of time (6 min) in recovery between sets, allowing for the greatest amount of lactic acid removal possible.

Now imagine moving directly from one exercise to the next “antagonistic” exercise without rest? If 3 minutes are required to perform each movement, the same amount of work would be performed in ½ the time, still allowing the muscles to recover adequately (3 min). If this is too demanding, there is no harm in resting briefly between sets, as the goal here is to ensure the same number of reps with each subsequent set.

Nervous Relaxation & Lactic Acid Removal

When nervous signals are transmitted to antagonistic muscles in an alternating fashion, resting muscle groups experience no residual impulses. This effect is only consistent with antagonistic muscle contractions. By ensuring that the muscle group(s) being trained together are antagonistic, as earlier mentioned, in effect there will be a forced relaxation in the resting muscle. In a sense, you are stretching the resting muscle group while the antagonistic group is performing contractions. This will allow for optimal collateral blood flow in the recovering muscle, lactic acid removal and conversion, and oxygen enrichment.

Since the cardiovascular system re-routes blood flow back and forth during antagonistic muscle functioning, the performance of a set for the second body part will actually draw interstitial fluid (along with the removed lactic acid) back into the vessels from the areas around the antagonistic muscle group.

Applicaton..

Taking all that into perspective, the goal is to ensure equal number of reps per set. Since lactic acid is a by-product of energy metabolism during contractions, the objective is to ensure removal of lactic acid. Since the muscles become impervious during contractions, we are faced with two options for removing it – stretching or resting. The methodology here is to incorporate both without sacrificing ample amounts of time in the gym. Knowing that our muscular system is arranged in opposing fashion (agonist/antagonist), and the fact that when one muscle contracts the opposing muscle (antagonist) relaxes, we arrive at this training principle. How you structure your routine is entirely up to you, but the following is a list of agonist/antagonist muscle groups (I will only focus on major muscle groups here):

• Chest (Pectoralis Major & Minor) / Back (Latisimus Dorsi)
• Rectus Abdominis / Spinal Erectors
• Oblique left / Oblique right
• Anterior Deltoid (front) / Posterior Deltoid (rear)
• Biceps / Triceps
• Forearm flexors (palm side) / Forearm extensors
• Quads (rectus femoris) / Hams (Biceps Femoris)

Remember, no matter what your fitness goals are, always strive to improve your performance. The faster you recover, the stronger you become. The stronger you become, the more you can push yourself. The more you can push yourself, the better your performance.