Mixed
Progressive resistance training for healthy adults requires periodized manipulation of load, volume, and intensity to overcome training plateaus and maximize strength, hypertrophy, power, and endurance.
To keep getting stronger or building muscle, you cannot do the exact same workout forever. Start with moderate weights (8-12 reps) for 2-3 days a week. Once you can easily do the top end of the rep range, increase the weight slightly (2-10%). As you get more advanced, vary your weights (some heavy, some light) and rest periods (longer for heavy lifts) to keep challenging your body. Don't just add reps forever; eventually, you must add weight.
The common theme of most resistance training studies is that the training program must be 'progressive' in order to produce substantial and continued increases in muscle strength and size... systematic variation has been used as a means of altering training intensity and volume to optimize both performance and recovery.
Why this rating
This is an American College of Sports Medicine (ACSM) Position Stand, representing a consensus of expert opinion based on a comprehensive review of the literature.
Source
Progression Models in Resistance Training for Healthy Adults
William J. Kraemer et al. · Medicine & Science in Sports & Exercise · 2002
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