Why some gym-goers skip legs while others neglect their upper body

The epidemic of muscle imbalances at the gym

Any regular at a commercial gym recognizes the pattern: women who hammer their back and triceps while their lower body languishes, and men who push their legs hard but whose upper body never takes off. It's not a subjective impression: in training geared toward aesthetic goals, asymmetry is the norm.

Those who focus on legs argue that they are half the body and that training them stimulates testosterone production, a hormonal effect backed by some studies. However, others point out that this long-term benefit is marginal, and that the workload doesn't justify neglecting the upper body.

At the other extreme, there are those who prioritize a wide torso and defined arms, relegating legs to minimal sessions. The explanation is usually aesthetic: "the torso shows, the legs don't so much." But the result, often, is unbalanced physiques that, despite strength in certain muscles, look lopsided.

The cost of ignoring symmetry

The problem isn't just visual. Uneven development can cause postural imbalances and injury risks. Shoulders rounded from hypertrophied lats without a stable core, or knees suffering from hypertrophied quadriceps without hamstrings, are typical examples.

Some trainers recommend not going to failure on every set and skipping a leg week now and then to maintain cardiovascular health, but the suggestion is controversial: many prescribe leg work at least twice a week.

Sporting preferences also play a role. Cyclists and soccer players have powerful legs out of necessity, but in classic bodybuilding gyms, chasing unbalanced extremes rarely makes sense. The question isn't whether to train one muscle group more, but why one chooses to neglect the other. And there, the answers tend to be more subjective than scientific.

The full breakdown of the hormonal and performance implications, with figures from specific studies, is in the original source. If you want to settle the question, go check the numbers.