Adding mass can influence the ways your muscles stress and strain during workouts. By adding it, more force is exerted which, in turn, leads to faster energy depletion. Both experiences can also affect your breathing pattern and how much oxygen you take in as you train.

Stressed muscles, increased breathing and depleted energy may sound negative for progress. But they are, actually, quite the opposite. As your body learns and adjusts to these factors, your strength, endurance, and cardio can see positive results.

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