Quick notes: every topic on one page
The short version of every deep dive on the site: the key idea, a memory hook and a link. Start here, then open the topics you want in detail.
Energy management
Phosphocreatine pays for each move, glycolysis for sustained hard effort, the aerobic system for the whole route. On measured indoor routes, aerobic and phosphocreatine did most of the work. Spark, burn, breath.
Hard grips squeeze the forearm's blood supply shut; letting go reopens it. Refill is fast at first, then slows. Squeeze shuts the tap, let go and it pours.
A half-time is how long it takes to win back half of what's missing: one gets you 50 % back, two 75 %, three 87.5 %. Measured about 8 s in elite and 47 s in intermediate adult climbers. Every half-time pays back half of what's still missing.
Larger arteries, more blood flow when a grip releases, muscle that uses oxygen better. In the studies this tracks training and ability, not youth. Wider roads, more trucks, a better factory.
Each extra half-time of rest buys half as much as the last. Leave when the improvement stops. Stay while it's paying, go when it flattens.
Below your critical force you can keep going; above it a limited reserve drains. Measured at about 41 % of maximum grip in adult climbers. Under the line you cruise, over the line you spend.
The pump depends on grip needed ÷ grip available. More weight at the same strength pumps you sooner; better footwork lowers the ratio as much as large strength gains. Body shape explained little in studies. It's the ratio, not the size.
Too fast drains the glycolytic reserve, too slow drains the forearm. Plan rests and clock checkpoints. Steady between rests, short at rests, check the clock.
Holds and how to use them safely
Every hold has a direction. Put your body where that direction works best. Find the direction, then put your weight on the other end of it.
Crimps load the pulleys far more than an open hand: an estimated 36 times more on the A2 pulley. The sharper the bend, the more the pulleys pay.
Adults usually strain pulleys; growing climbers can crack growth plates. Know which pain means stop. Pain means stop.
In growing fingers the cartilage plate at the middle joint is the weak point, and repeated hard crimping can crack it. No campus boards while growing. Pain at the back of the middle joint means stop.
Warm up, choose the gentlest grip, use your feet, build up gradually, stop at pain. Warm, open, feet, gradual.
Resting positions
Rest before you're deeply pumped (about 3–4 on a 0–10 scale) and save your best rest for just before the crux. Plan rests from the ground. Rest while you can, not when you must.
Hang from the skeleton, hips close to the wall, so the hands grip less. Hang from the bones, hips to the wall.
Drop knee, stem, knee-bar, heel hook and toe hook let the legs hold you. Legs hold, hands rest.
Shake with the arm low beside the body: measured 32 % faster re-oxygenation than with the hand by the hold. Swap every few seconds. Low and loose, then swap.
Raised overhead, the forearm refilled 2.44 times more slowly in one study. Hang the resting arm low and shake it loosely. Below the heart, loose, and shaking.
A rest is a hold you can grip lightly. Stay while you're still improving. Getting better? Stay. Flat? Go.
Movement and body position
Quiet, precise feet; flags for balance; hips turned in to reach with straight arms. Quiet feet, straight arms, turn the hip.
Clip from good holds with the quickdraw at waist to chest height. Never climb past a clip to save energy. Good hold, waist to chest, quick and clean.
Start here, scenarios, drills and research
Whole line, crux, rests, clips, hands, feet; then climb it in your head. Read it, then climb it in your head.
Measured, coaching practice or model: check the label before you trust the number.
Five situations on the wall with choices and consequences.
Nine drills, each with a goal, steps, what to measure and dose, plus a printable log sheet.
Every cited study: who was tested, the numbers used here, and the limits.
Wearable near-infrared sensors track muscle oxygen while you climb. Compare yourself with yourself: same spot, same routine.
The evidence
- Coaching practice These are summaries. Each linked page labels its claims and gives the sources.
- Measured Numbers quoted here (41 %, 32 %, 36 times) are from adult studies; see the linked pages for who was measured.