How much weight, how many sets, how often?

Very good from one to six reps — usually within about 3% of a tested max — and progressively worse above that. Beyond ten reps, muscular endurance starts to matter more than maximal strength, and two lifters with the same true max can produce very different rep counts at the same load. That is why this shows three formulas rather than one.

They fit different curves to the same relationship. Epley is linear in reps, Brzycki is a hyperbola that blows up as reps approach 37, and Lombardi is a power function. At five reps they land within a couple of percent of each other. At twelve, Brzycki reads noticeably lower than Epley, and the spread between them is a useful honesty check on the estimate.

Roughly 80% of your estimated one-rep max, though the honest answer is whatever gets you to eight reps with one or two left in reserve. Percentage tables are a starting point, not a prescription: the same 80% feels very different on a deadlift than on a lateral raise, and it drifts with fatigue across a training block.

Most people grow on 10 to 20 hard sets a week per muscle group. Beginners see results at the bottom of that; advanced lifters usually need the top of it. Arms tolerate less absolute volume than back or legs, partly because they already work as synergists in every pressing and pulling movement you do.

MEV is the minimum effective volume — the fewest hard sets a week that still produce growth. MRV is the maximum recoverable volume — the most you can do and still recover from before the next session. The productive range sits between them. Below MEV you maintain; above MRV you accumulate fatigue faster than you adapt.

No. Only hard working sets taken within a few reps of failure count. This is the single most common reason people believe they are doing far more volume than they really are: a session logged as twenty sets often contains eight warm-ups and back-offs, leaving twelve that actually drove adaptation.

For equal weekly volume, splitting it across two or three sessions generally wins. The mechanism is quality, not magic: the last sets of a twenty-set chest session are performed with badly degraded output, whereas seven fresh sets three times a week are all productive. Once you exceed roughly ten hard sets for a muscle in one session, adding more gives very little.

Roughly 24 hours for abs, 36 for arms, 48 for chest and shoulders and 60 for legs and back, after a moderate session. A genuinely hard session multiplies that by about 1.35. Those are working figures for programming, not physiological constants — the actual repair timeline varies with the exercise, the eccentric load and how novel the stimulus was.

Yes, and the effect is real rather than an excuse. This model adds about 10% after 35, 20% after 40 and 40% after 50. The usual practical consequence is not training less but training each muscle slightly less often, with the same weekly volume spread over a longer cycle.

A great deal. Under six hours a night stretches the recovery window by roughly 30% in this model, and under seven by about 15%. Growth hormone release is concentrated in deep sleep and protein synthesis follows it, so short sleep does not merely make training feel harder — it lengthens the time until the muscle is ready again.

Mild soreness is not a reason to skip a session; significant soreness is a reason to reduce its volume. Soreness and readiness are only loosely related — you can be sore and recovered, or unsore and under-recovered. Performance in the first working set is a far better signal: if it is well below normal, cut the session short.

Both, without adjustment. All three multiply your load by a factor that depends only on the rep count, so the unit passes straight through. A 225 lb set of five and a 102.06 kg set of five produce exactly the same estimated max in their respective units.