Why Running or Biking Before Lifting Is Good for You

You’ll often see fitness influencers sing the praises of the “run into a lift,” or knocking out a few miles on the roads before heading to the gym to strength train.

The conventional wisdom is that a bit of aerobic exercise gets the blood pumping, making you more primed and effective for anaerobic exercise. I’ve long sworn by the practice myself. And not just as a warmup, but as a matter of convenience — I often run straight to the gym from my house.

Recent research, though, suggests that the science is even more robust than “running warms up the body.” According to a study published in Scientific Reports, twenty minutes of cardio before a lift can actually catalyze increased muscular growth, in a way that lifting alone can’t match.

Researchers at Stockholm’s Swedish School of Sport and Health Sciences specifically set out to determine whether working out one’s legs and lungs would have any impact on a subsequent arm workout. They recruited eight male volunteers, who were tasked with performing an intense interval circuit on a stationary bike (pedal hard for four minutes, rest for three minutes, repeat five times), then lifting with upper-body weight machines.

They then came back later and only did the upper-body training. While the bloodwork indicated muscle growth after each version of the experiment, there was more “protein and gene activity” following the lower-body endurance/upper-body training hybrid, as The New York Times reported.

The lead author, Dr. Marcus Moberg, said: “The most fascinating finding is that some biochemical factors evoked by the leg endurance exercise entered the bloodstream and were then able to influence processes in a completely different group of muscles, and in a way that seems to be beneficial for the training adaptations in the arms.”

In other words, training your legs is good for your arms. And it’s especially beneficial directly before you plan to train your arms. For those who’ve long assumed that endurance pursuits get in the way of gains, this is your sign to switch up the routine, and either hop on the bike, or lace up some shoes and get back on the roads.