The Acute Effect of Increasing Resistance Training Workload Volume on Muscle Damage Markers and Performance in Heavy Resistance-Trained Youth Athletes

When young male rugby players switch from heavy strength training to a higher-rep, lighter-weight muscle-building routine, they feel more sore and show more signs of muscle damage in their blood tests.

When young male rugby players switch from heavy lifting to doing more reps with lighter weights, they feel more muscle soreness and show signs of more muscle damage in blood tests.

In young male rugby players who lift weights, doing high-rep, lighter weight workouts leads to worse sprinting and agility performance for up to two days compared to low-rep, heavy weight workouts.

Young male rugby players who do high-volume muscle-building workouts might see a small drop in their jump performance compared to those doing heavy strength training — but the results aren't super clear because different equipment was used.

For young male rugby players who lift weights, doing more reps to build muscle might slightly hurt their jumping ability compared to training for pure strength — but the measurement wasn't perfect, so we're not totally sure.

For young male rugby players who lift weights, doing high-rep, lighter weight workouts seems to slow them down and make them less agile for a day or two more than doing low-rep, heavy weight workouts.