Stretch the Opposing Muscle

A team of Brazilian researchers, reporting in Research in Sports Medicine, found that stretching the pecs prior to doing seated rows leads to doing significantly more reps in that exercise, but it may also have other, unforeseen benefits.

Muscleheads, at least those who speak in words with more than one or two syllables, often refer to agonist and antagonist muscles. These terms simply refer to muscles that act in concert. For instance, when you do a biceps curl, the biceps contract and its antagonist, the triceps, relaxes.

This applies to several major muscle groups throughout the body, including the quads and their antagonist, the hamstrings, and the lats and their antagonist, the pecs.

Many of us have heard that stretching the antagonist of the muscle you're working prior to doing a set can lead to doing more reps or more weight, but it's largely anecdotal because there haven't been that many studies to confirm the phenomenon. Now, thanks to the Brazilian researchers, we found out that it definitely works, at least as far as stretching the pecs and seated-row performance.

What They Did

Here's the protocol the researchers used:

  1. Ten experienced lifters were recruited to train their lats on two separate occasions by doing seated rows.
  2. Electrodes were attached to their muscles.
  3. The subjects did 3 sets with approximately their 10 RM.
  4. They rested for 2 minutes between sets.
  5. The first time they conducted the experiment, they didn't stretch at all between sets.
  6. The second time they conducted the experiment, they held a passive pec-stretch for 40 seconds before the first set and in-between the subsequent sets.

Results

Passive stretching increased electrical activity in the lats and the biceps, but didn't have any effect on electrical activity in the pecs. Test subjects were subsequently able to do more reps in the seated row exercise.

Graph

The researchers concluded, "The antagonist stretching applied during the inter-set period showed greater repetition performance and agonist muscle activation in the seated row exercise compared with a passive rest period between the three sets."

Of course, it's also interesting what the researchers didn't conclude. You may have noticed that the passive stretching of the pecs increased electrical activation not only in the lats, but the biceps, too. Would stretching the pecs for 40 seconds in-between sets of curls have the same beneficial effect on biceps? Try it yourself and see.

While the subjects in the study accomplished a stretch by putting their hands behind their head while the researchers pulled their elbows back, you can stretch them yourself simply by standing in the middle of a doorway, bending the elbows at a 90-degree angle, placing the forearms on each side of the doorway, and leaning forward.

Doorway Pec Stretch

Alternately, you can pick up a pair of light dumbbells, lie on a bench, and extend your arms to the sides as if you were going to do a flye and hold that position for 40 seconds.

Related:  Arnold's Agonist-Antagonist Training

Related:  Best Back and Biceps Exercises