The library
Isolation

Backpack Shrug

Trains traps first, with real work landing on forearms.

Muscle contribution per set

Traps1
Forearms.30

These are the weights Heatwayve's volume audit actually computes with — deliberately conservative, so compounds don't masquerade as full coverage. A 0.5 means a set counts as half a set for that muscle: meaningful help, not a replacement for direct work.

Tempo

2down
0pause
1up
1squeeze

Scapular elevation with a top squeeze; traps respond to the hold more than the range.

Loaded pack held at the sides; shrug straight up, squeeze, no rolling.

Derived from tempo research on this movement class.

How Heatwayve progresses it

Progresses by load in +0.5kg steps. Isolation work is where the honest-volume ledger pays off — compounds alone don't cover it.

Train with intention. Open Heatwayve — it prescribes the weight, watches the reps, and does this arithmetic for every set you log.