It's just easier and more aesthetic to see your muscles if your skin is a little darker. For that reason, you need to safely tan yourself on a regular basis to make sure your muscles are looking their best.Don't forget under the arms. Avoid sugary sports drinks and other fluids during your workouts.
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But taking every set past muscle failure is counterproductive and won't maximize muscle gains. Instead, take just 1-2 sets of an exercise to complete muscle failure. In fact, on all sets in which you train fairly heavy—designated as sets in which you do 6-8 reps to muscle failure—rest a bit longer than normal to ensure that you're not fatigued from the previous set.
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