The evidence behind Aretia.

Muscle growth rises with the number of hard sets per muscle per week, with roughly ten sets a week a productive anchor and more adding benefit up to a point.

The weekly set targets per muscle, and the "in the productive range" band the analyser scores against.

Size and strength both keep increasing as weekly sets increase, with diminishing returns that are sharper for strength. Counting an indirect set as half of a direct set predicted the results best.

The diminishing-returns shape of the volume targets, and the rule that a secondary muscle earns half a set while the primary earns a full set.

At matched weekly volume, training a muscle at least twice a week grew it more than training it once a week.

The rule that every muscle is trained at least twice a week, and the analyser flag for muscles trained only once.

Muscle growth was similar across light and heavy loads taken to failure, while one-rep-max strength favoured the heavier loads.

Heavier loads and lower reps on the main compound for its strength carry-over, with higher reps on the isolation work.

Training to momentary failure was not better for growth than stopping a few reps short, as long as the sets were taken close enough to failure.

The target of roughly zero to three reps in reserve on each set, rather than grinding every set to failure.

Over eight weeks, progressing by adding load at a fixed rep count and progressing by adding reps at a fixed load produced similar gains in size and strength.

The double-progression rule the workout screen uses to suggest today's target: top the rep range and the engine adds load, stay inside the range and it adds a rep.

Across 246 competitive strength and physique athletes, deloads were used by all of them, ran every 5.6 weeks on average, lasted about six days, and were taken to manage fatigue.

The default cadence offered when the deload feature is enabled: four hard weeks then one deload week.

An international expert panel defined a deload as a period of reduced training stress used to mitigate fatigue and prepare the lifter for the next block of training.

The working definition behind the deload-week banner: same lifts and loads, half the working sets, with fatigue dissipation as the goal.

Full range of motion produced larger gains in strength and lower-limb size than partial range training.

The preference for exercises trained through a full range.

Curls trained through the lengthened, extended elbow angles grew the elbow flexors more than the same range worked at the shortened angles.

Favouring exercises that load the muscle in a stretched position.

Overhead triceps extensions, which hold the long head at a long length, grew it more than pushdowns done with the arm by the side.

The same lengthened-position preference, applied to exercise choice.

Gains in lean mass kept rising with protein up to about 1.6 g per kg of bodyweight a day, then levelled off.

The daily protein floor and target.

Dieting at about 0.5 to 1% of bodyweight a week, with high protein per unit of lean mass, protected muscle while losing fat.

The rate of weight loss on a cut and the higher cut-phase protein.

Losing weight slowly, around 0.7% a week, kept lean mass and built strength, while losing faster cost muscle.

The default cut rate.

A modest surplus aiming for a quarter to a half percent of bodyweight a week limited fat gain while supporting muscle growth.

The default bulk rate and surplus.

Lifting alongside running cost some muscle and strength, while cycling did not, and the interference grew with more frequent and longer endurance work.

The low-impact, moderate cardio prescribed on a cut.

Overhead pressing drove the highest front-delt activation of the lifts measured, while the lateral raise led for the side and rear delt.

Matching shoulder exercises to the head they train best.

Upper-chest activation peaked at a 30-degree incline. Past 45 degrees the front delt took over and chest activation fell.

The incline guidance on incline pressing.

At a heavy load, the barbell hip thrust drew higher peak glute activation than the back squat or the split squat.

The role of the hip thrust as a direct glute movement.

A regression equation that estimates resting energy expenditure, named by the Academy of Nutrition and Dietetics as the standard for adults.

The starting point of the calorie and macro calculator.