Muscle Hypertrophy

Strength training typically produces a combination of the two different types of hypertrophy: contraction against 80 to 90% of the one repetition maximum for 2–6 repetitions (reps) causes myofibrillated hypertrophy to dominate (as in powerlifters, olympic lifters and strength athletes), while several repetitions (generally 8 – 12 for bodybuilding or 12 or more for muscular endurance) against a sub-maximal load facilitates mainly sarcoplasmic hypertrophy (professional bodybuilders and endurance athletes).[citation needed] The first measurable effect is an increase in the neural drive stimulating muscle contraction. Within just a few days, an untrained individual can achieve measurable strength gains resulting from "learning" to use the muscle.[citation needed] As the muscle continues to receive increased demands, the synthetic machinery is upregulated. Although all the steps are not yet clear, this upregulation appears to begin with the ubiquitous second messenger system (including phospholipases, protein kinase C, tyrosine kinase, and others).[citation needed] These, in turn, activate the family of immediate-early genes, including c-fos, c-jun and myc. These genes appear to dictate the contractile protein gene response.[citation needed]

Progressive overload is considered the most important principle behind hypertrophy, so increasing the weight, repetitions (reps), and sets will all have a positive impact on growth. Some experts create complicated plans that manipulate weight, reps, and sets, increasing one while decreasing the others to keep the schedule varied and less repetitive. It is generally believed that if more than 15 repetitions per set is possible, the weight is too light to stimulate maximal growth.[1]
Anaerobic training
Main article: Anaerobic exercise

Experts and professionals differ widely on the best approaches to specifically achieve muscle growth (as opposed to focusing on gaining strength, power, or endurance); it was generally considered