Leg Exercises: Leg Extensions - Before or After Squats?

Maximal leg muscle growth requires you to recruit as many muscle fibers as possible during leg exercises, which is the reason many bodybuilders perform squats first—because the exercise utilizes many different muscle fibers. For gaining muscle size, your training goal should be to recruit as many motor units as possible during leg exercises to get the fastest results for muscle growth.

This has been the resistance training way of life for decades, but recently a study in the Journal of Medicina Sportiva found just the opposite of what has been preached for so many years about doing large muscle groups first. The research paper was a critical review on exercise sequence and muscle growth and has challenged the size principle theory. The authors reported that two new studies showed no significant difference between groups in strength gains for any of the leg exercises or any significant difference in muscular hypertrophy when small muscle groups were performed first compared to large muscle groups.

The key finding was that when repetitions were standardized for workouts comparing small vs. large muscle groups performed first, the results were the same. The research paper went on to report that many studies that have examined small vs. large muscle groups being performed first failed to control for repetitions completed. The reviewer noted that some of these studies reported that significantly fewer repetitions were performed in subsequent sets of an exercise when they were performed later in a resistance-training session, compared with when they were performed earlier in the session.

The lead author concluded, “There is very little evidence to suggest that any specific sequence of exercise affects strength gains or muscular hypertrophy.” As long as volume remains equal for workouts, it should make very little difference which exercise is performed first.

Ralph N. Carpinelli. DOES THE SEQUENCE OF EXERCISE IN A RESISTANCE TRAINING SESSION AFFECT STRENGTH GAINS AND MUSCULAR HYPERTROPHY? A CRITICAL EXAMINATION OF THE EVIDENCE. Medicina Sportiva. Med Sport 17 (1): 40-53, 2013