A systematic review of eight variation studies and a 12-week trial of 49 lifters answer the exercises-per-muscle question the way the evidence can: by what variation does and does not add.

Two meta-analyses on inter-limb asymmetry - one on whether it costs performance, one on how large it normally is - replace the poster threshold with numbers.

A meta-analysis of 18 trials and a head-to-head push-up versus bench press study show that moving your own weight is resistance training - provided the leverage is set to make it hard enough.

A lever, a cam and a chain load the muscle in different places. A 2026 network meta-analysis of 694 lifters says that matters for maximal strength (SMD 0.62), barely for power, and not at all for hypertrophy.

First pull, scoop, second pull, catch - and the force-plate data behind each. Peak power lived at 60 percent, not 90, the optimal load tracked relative strength, and a 2025 network meta-analysis ranked cleans first for sprinting, in probability only.

A Bayesian network meta-analysis of 178 randomised trials plus an umbrella review of 14 meta-analyses turn programme design into four decisions. Here is the recipe, with the numbers behind each step.

How strong is strong? Two recent analyses of more than 800,000 powerlifting competition entries give the first properly sourced benchmarks for the squat, bench press and deadlift by sex, age and body weight, and show how those benchmarks have drifted since 2000.

Aerobic base and maximal strength hold for about a month after you stop training them; speed and reactive power fade within a week. Those durations are the logic behind which block comes first and which comes last.

Squats, deadlifts, rows and carries all tax the spinal erectors, so a split can load them daily by accident. What the recovery and frequency evidence supports for spacing spine-heavy work.

Traditional periodization develops several qualities at once across a long season; block periodization concentrates one at a time. What the trials say about which works, and why experience level changes the answer.

HIIT or steady-state — which one costs you less strength? A 2016 work-matched trial and a 2021 meta-analysis of 43 studies say the question is wrong. Here is what actually interferes, and what to do about it.

One hard set or three? A six-month trial with 1, 3 and 5 sets, two meta-analyses and a 2026 dose-response analysis of 2,058 lifters show where the extra sets pay off - and where they do not.

Two days or three? Linear, undulating or block? The trials behind the rules of thumb are small and old. Three meta-analyses from 2018 to 2026 show what survives - and that the answer depends on how trained you are.

Six sessions of 30-second sprints doubled cycling endurance in two weeks. What SIT does to VO2max, muscle and body fat - with the numbers from a 55-study analysis - and why the rest interval is not a detail.

Does lifting make distance runners faster? A 12-week trial in well-trained runners, a study of hamstring-to-quad balance in female runners, and two 2024 meta-analyses of 38 studies show what heavy lifting does to economy and race time.

Will lifting stunt a child's growth? The injury rates say supervised weight training is among the safest things a young athlete does, and a 2020 umbrella review of 14 meta-analyses puts numbers on what it builds.

One minute or three between sets? Four trials in trained men, two systematic reviews and a 2024 Bayesian meta-analysis draw the line at about 60 to 90 seconds - and show why strength and size answer the question differently.

Alternating heavy and light days is the oldest trick for getting past a stall. The trials and a 35-study meta-analysis say it works - for maximal strength, in trained lifters, with a moderate effect - and does nothing extra for muscle size. Here is how to structure and log it.

Wide grips lift more and load the shoulder more; narrow grips do the reverse. The sticking region is a mechanical event, not a weakness. Here is what the biomechanics and injury literature say about grip, range of motion and shoulder safety in the bench press.

One school says the low back should be stiffened and spared; the other says it should be isolated and strengthened like any other muscle. The trials favour training the extensors for pain in chronic low back pain - with low certainty, small effects and a clear place for both ideas.