Aerobic Endurance on the Hangboard
You’ve just passed the crux. The rest of the route should be easy for you. Everything looks like you’re sending. But one thing isn’t right. The pump in your forearms doesn’t want to go! After a minute on the jug of the rest, you start climbing again and the tiredness kicks in instantly. At the last dynamic movement before the anchors, your fingers reach the hold and don’t close. You take the big fall and get caught by the rope.
That is not a strength problem. Your fingers were strong enough for those holds ten minutes earlier. It is a blood flow problem, and the hangboard is a good tool to fix it.
Picture from Yves Gravelle.
Blood flow
Getting the most out of rests, climbing long easy sections, and recovering between tries all require good blood flow in the forearms. Climbing is intermittent by nature: you have to relax your grip to move to the next hold, and each of those brief releases is a chance for blood to get in, deliver oxygen, and carry metabolites out. How well you use those windows depends on capillary density in the forearm.
Aerobic capacity is seldom trained by climbers and yet it decides how much of your strength is still available on the last move.
Two different qualities, two different intensities
This is where most endurance training goes wrong, and it is worth being precise, because “endurance” gets used for two adaptations that need different loads.
| Quality | Intensity | What it changes |
|---|---|---|
| Aerobic capacity | ~20–35% of max | Capillary density, blood flow, recovery between and during efforts |
| Strength endurance | ~60–80% of max | How long you can hold a hard position before failing |
Around 25% of maximum voluntary contraction is often cited as the ceiling where aerobic metabolism is still the main energy source. Go much above that and you start restricting your own blood flow, which is the opposite of what you came to train.
A 2022 randomised trial in Frontiers in Sports and Active Living put 54 experienced climbers through four weeks of hangboard work, twice a week, on force-instrumented edges. The submaximal groups trained 10 second hangs with 6 second rests at 60% and 80% of maximum. Both improved their ability to hold force after fatigue, from around 63% to 79%. Neither gained maximum strength. The group training at maximum gained 14.3% strength and improved neither endurance measure.
The intensity you pick selects the adaptation you get. That is the whole game.
Endurance on the wall
Traditionally, climbers train endurance on the wall with long sessions or specific exercises. Three that work: climb four routes without rest, four times over; do ten boulders back to back; climb circuits on a training wall. For each one, aim for an intensity as continuous as possible. The goal is to link as many movements as you can, well below your limit, without having to stop.
Wall work is the most specific way to do this, and it should stay the bulk of your endurance training.
Endurance on the hangboard
The hangboard adds three things the wall does not: it is fast, the intensity is controllable, and it is almost purely physical, so a bad day of climbing movement doesn’t ruin the stimulus.
For aerobic capacity, hang intermittently at 20–35% of your maximum, 10 seconds on and 5 seconds off, for 5 to 10 minutes per set. It should feel easy for the first two minutes. If you are gripping hard, the load is too high.
To find that load:
- With a force plate, pull as hard as you can for 5 seconds to get your max, then take 20–35% of that number and hold it. Watching the number is the point — the target here is a narrow band, and it is very easy to drift above it as you fatigue.
- Without one, use the minute test. Pick a load you can hold continuously for a full minute with effort left over. That is close enough to the right band to train in. Keep your feet on the ground and take weight off the holds until you find it.
Partial hangs, with your feet still on the floor, make this easier to dial in than full hangs with added or removed weight. You can adjust mid-set instead of stopping.
When to start?
Endurance work will make you tired. Don’t put it before a climbing session or a strength session — you will just do both worse.
A block of it is useful to prepare for a strength cycle, before a climbing trip, or before an event. It also works without a dedicated focus, one day a week, kept easy. Because the intensity is so low, it recovers fast and stacks well with everything else.
