Watching an expert model plus feedback on your own video improved Olympic-lift technique in three novices, and video feedback helped young lifters' snatch. Watching alone, without feedback, has barely been tested in lifting.

In 30 trained weightlifters, performing their main snatch error on purpose, exaggerated, improved technique more than direct instruction, and the gain held at one week. It is untested on the squat, bench press or deadlift.

As muscles grow, their fibres pennate more steeply and force per unit of size falls in strength athletes, yet pennation is also how a muscle packs in more fibres: a trade-off, not a fixed ceiling.

In failed heavy squats the hip was the joint that most consistently ran out of energy, but in some lifters the knee was the weak link, and under fatigue the load shifted towards the hips and lower back.

In resistance-trained men squatting as fast as possible, muscle activation rose with load but not linearly, and the heaviest load still produced the most. What intent can and cannot replace.

Two small EMG studies disagree: one found greater activation of every muscle measured with hips and knees flexed, the other found no difference with the legs in the air. Why, and what it means for your bench.

In untrained adults, standing calf raises grew the gastrocnemius more than seated calf raises over 12 weeks, while soleus growth was similar either way. What the evidence does and does not show.

A study of five female and five male athletes found that muscle activity patterns shifted with load differently in women and men; a larger mixed-sex study found no sex differences at 75% of 1RM. What the evidence can and cannot tell you.

In a small EMG study the reverse hyperextension produced greater peak activity than the hyperextension in the erector spinae, gluteus maximus and biceps femoris. What that does and does not tell you about training.

Low-load glute exercises before jumping raised jump power or height in two small studies, sprint results were mostly unchanged, and the one study that measured glute EMG found no change.

In elite male powerlifters, lean body mass, limb proportions and shoulder flexor strength predicted 59% of the variance in body-mass-adjusted bench press, while technical factors did not correlate. Here is what the evidence supports.

In competitive weightlifters, back squat and overhead press 1RM together predicted split jerk 1RM closely. Overhead press strength alone correlated strongly with the split jerk, more so in men than women.

EMG studies show clear differences between shoulder exercises in which deltoid head works hardest. A training study in the glutes suggests that higher EMG does not automatically mean more growth.

In college football players, reps to failure with dumbbells predicted barbell bench 1RM almost as well as reps with a barbell. Barbell and dumbbell training produced similar strength gains in a 12-week trial.

In 11 trained men, arm, torso and shank length did not clearly predict conventional deadlift mechanics. Sumo and conventional differ in joint angles, work and muscle activity, but no study we read tested which body type suits which style.

Experienced strongmen produced less bar speed and power with a log than with a clean and jerk at the same load, with more trunk and hip motion. In the push press, a barbell produced 1.8–4.4 times greater propulsive outputs than a log, with a larger gap against the larger log.

Low-bar squats shift the movement to the hips with more forward lean; high-bar keeps the torso upright and goes deeper. Muscle-activation claims are hedged in the review, and at maximal loads elite powerlifters and weightlifters squat more alike than their bar positions suggest.

Across 55 trials, loaded resistance training improved range of motion (ES 0.73) and matched stretching; combined lifting and stretching did no better than stretching alone. Bodyweight-only training did not help.

Two biomechanics studies. In rugby athletes at 70–85% 1RM, a wide stance raised the hip-to-knee extension ratio and knee adduction moments while a narrow stance bent the knee more. In experienced lifters, the narrow squat drove more gastrocnemius activity and the wide squat produced greater tibiofemoral and patellofemoral compression.

Each leg produces less force when both push together, except in weightlifters, where it produces more. The deficit is neural, affects only matching muscles, responds to stimulating the other limb, and appears to follow training history.