Why gain muscle?

• "total mortality was significantly lower in the fourth quartile of muscle mass index compared with the first quartile"

How much muscle will I gain?

For men:

• Year one: 20-25lb, 9-11⅓kg
• Year two: 10-12lb, 4½-5½kg
• Year three: 5-6lb, 2½kg
• All subsequent years: minimal amounts

So overall about 14-16kg above baseline

For women: Half the above.

How to gain muscle?

Do three things and you'll gain muscle:

• Eat a caloric surplus
• Eat a protein surplus
• Expose your muscles to high levels of tension (i.e. lift)

How much caloric surplus?

14-16 kcal per pound of bodyweight is your baseline

• Year one: 175 calories/dayover baseline
• Year two: 120 calories/day over baseline
• Year three: 60 calories/day over baseline

Sources: https://bodyrecomposition.com/muscle-gain/calories-for-muscle-gain

How much protein?

2.5-3.0 g per kilogram of bodyweight

Source: https://bodyrecomposition.com/nutrition/protein-requirements-growth

How much/what kind of muscle tension?

You need high tension but also the right volume. High tension means 70-85% 1RM. No need to lift more than 85% of 1RM.

doi:10.1249/00005768-197500740-00003 and doi:10.2165/00007256-200737030-00004 are the classic papers on this.

30-60 reps per session: 3 sets of 10, and sometimes two different exercises per bodypart

5×5 is fine too; things like the Madcow or Stronglifts 5×5 give about the same muscle-tension as 3×10, and muscle tension is the whole point.

Train twice per week. The research is clear on this. Three times is not better than twice.

More complicated ways of getting that muscle tension

Heavy negatives (130% of 1RM) work but volume should be very low: 14-16 seconds of tension per session

Isometrics: A study doing 10 seconds of isometrics, three times a day (30s/day), six days a week, had the best gains in bicep size

I said three workouts a week is not better than two, but there might be an exception in the first week of a mesocycle. So a mesocycle would be: train four times a week for one week, train twice a week for five weeks, rest a week, repeat.