Optimize: Strength & Muscle

The builder, and the only lever that carries the whole goal. Progressive overload is what grows muscle and strength: about one hard set, 2 to 3 times a week, already added ~26 lb across the main lifts; training a muscle twice a week beats once; each added weekly set grows a muscle ~0.4% more. Load matters less than effort (light and heavy build similar size to failure), and you need not train to failure. Works into the 80s and 90s: frail 87-year-olds gained 113% leg strength in ten weeks. Men and women over 50 adapt alike.

The fastest, cheapest win, but only alongside training. Protein plus lifting added ~5.5 lb to a one-rep max and ~0.7 lb of muscle; the benefit plateaus near 1.6 g/kg/day. Older adults need more (1.0 to 1.2+ g/kg vs 0.8). Plant and animal protein build the same lean mass once total intake is matched, and timing around the workout adds nothing once the daily total is met. Protein without training changed nothing across 36 trials in older adults, so it is a partner to lifting, not a substitute.

The most-proven supplement here. Creatine plus training beat training alone across ~100 trials, and added ~3.1 lb more lean mass in adults 57 to 70; it raises strength in older women too. Plain monohydrate at ~3 to 5 g/day is all you need: no loading phase required (a month of daily dosing saturates), and the pricier forms did not outperform it.

The empowering fine print of resistance training: it takes less than people fear. One hard set 2 to 3 times a week added ~26 lb across the main lifts; a single set built most of the available strength (multiple sets add ~46% more, and reward size more than strength). Gains max out near 60% of max load for beginners, 80% for trained lifters; push-ups matched to a light bench press built strength about as well; and one set once a week held on to strength for up to 32 weeks.

Loaded carries and weighted-vest training are real resistance work: nine months of weighted-vest exercise raised older women's leg strength 16 to 33% and improved power. An accessible on-ramp that loads the whole body without a gym.

Power and plyometric training, aimed at the fast-twitch power that fades faster than strength with age (~8.5% over three years). Plyometrics raise jump height ~8.7%, and power training edges slow lifting for physical function in adults over 60. Add it to, not instead of, heavy lifting.

For muscle you cannot train voluntarily: NMES cut ICU-acquired weakness (OR 0.22), added ~128 ft to the six-minute walk in severe COPD, and sped early quad recovery after knee replacement. For a muscle you can already train, it adds nothing over ordinary exercise, so it is a clinical/rehab tool, not a shortcut.

Reconsidered per directive: not a general strength lever. The small strength gain (SMD 0.17) sits almost entirely in people who were deficient or old. If you are replete, do not expect it to build strength; correct a genuine deficiency and stop there.

Promising but thin: the headline bench-press result is one manufacturer-funded trial (Ixoreal/KSM-66) in 57 untrained young men, the population where everything works. Not yet shown in trained lifters.

A mitophagy activator with a single manufacturer-funded (Amazentis) trial showing ~12% strength and better endurance in middle-aged adults; the endurance/mitochondrial signal is clearer than the strength one. Independent replication is missing.

Not a muscle-building protein: collagen did not raise muscle protein synthesis while whey did. Paired with resistance training it added a little fat-free mass and strength in small trials. Useful for connective tissue, weak for muscle.

One small trial (400 mg/day, five weeks) in active seniors, and its endpoint was handgrip strength, which is a tracking marker rather than whole-body strength. Preliminary.

Honest null for the goal: ibutamoren (MK-677) adds ~2.4 lb of fat-free mass over a year, much of it fluid, with no gain in strength or physical function. It changes the scale, not what you can do, and is an unapproved drug, not an empower-first lever.

A gentle on-ramp for frail or deconditioned starters, not a strength or hypertrophy builder. Its measured gains are trunk flexibility and grip strength (a marker). The claim that it beat resistance training on a sarcopenia performance score is implausible and rests on a single weak trial; do not surface it as a strength lever ahead of lifting.

Dasatinib plus quercetin improved walking speed and strength in aged mice. Animal-only; nothing to act on for people yet.