Rock climbing

How to Train Endurance for Rock Climbing

This is part one of our five-part series, Learning to Train: A Complete Guide to Climbing Training.

The problem

Climb a route below your limit always feels pompous, or you find it difficult to recover in the middle of a route, even when resting on a pitcher or climbing on easy terrain.

The solution

Train local endurance with ARC sets to climb longer and recover easier.

How it works

Local stamina is your ability to stay on the wall for long periods of time at a certain level. The main benefit is that it increases the level of difficulty you can rest at. If you can climb 5.10 without feeling pumped, then hitting a 5.10 climbing section after a crux provides an opportunity to shake off and recover. You will feel fresh for the next challenging section. However, if you don’t have that level of stamina and reach the next crucial point tired, you’re probably ready for a ride.

Although a 5.12 climber can find easy 5.10 routes, that doesn’t mean they can climb 5.10 indefinitely. It just means it’s not that pumped at the end of a single 5.10 route. A high level of local stamina means that climbing below a certain level for 45 minutes at a time, or even longer, will not get you pumped.

Local endurance is the ability of a muscle group to sustain an effort over a period of time. When you climb, your forearms fail because blood isn’t reaching muscle tissue, but it’s not because your heart isn’t pumping fast enough. Instead, blood struggles to reach your forearms, which creates the pump. This means you will need to train your forearms rather than your general cardio abilities.

Feeling pumped means your arm muscles aren’t getting enough oxygen-rich blood, which helps the muscles create the chemical ATP efficiently. ATP is needed to release muscle fibers after they have contracted, so if there is not enough ATP available, your muscles cannot relax. This is why you have trouble opening and closing your hands when you’re really pumped. Once the muscle fibers become blocked, they compress the tiny blood vessels (capillaries) in your forearms, which means that less oxygen reaches the other fibers as well and the pump develops in a vicious cycle. When zero blood reaches your muscles, they lock up and you fall.

The goal of local endurance training is to prevent this blood supply shutdown, by delivering ATP to your forearms, so the fibers can relax and flex with each movement.

How to train local endurance

The most popular form of local endurance training for climbers is called ARC training, which stands for aerobic, respiration, and capillary action. The goal of ARC training is to create more tiny blood vessels (capillaries) in your forearms. By climbing lots of terrain below your limit, you will actually grow more small blood vessels, and existing ones will become larger. Both changes will make it harder to fit a pump, which means you can climb longer and recover faster.

ARC training is done by climbing easy terrain for 15-45 minutes at a time while maintaining a very light pump. Common methods include traversing a boulder wall or climbing up and down lanes on a toprope or auto belay without breaking loose.

First, choose a type of terrain to cover. Vertical to slightly overhanging terrain is best because it keeps some weight on your arms, but not too much. If you can find a route or section of wall with multiple angles within this range, even better. Training from different angles will allow you to refine your technique and break the monotony of long reps.

Next, you will need to determine the difficulty of your target route or crossings. If you haven’t done ARC type training before, start at 5.6 or 5.7 and increase the rating as needed. If you’re traversing or don’t have a level route to climb on, use holds that create a light pump that you can sustain for a long time. The climbing should be fairly continuous, with no difficult movements that could cause a fall. It is better if you can move without stopping to shake yourself frequently. The idea is to climb and move, not just on the wall, for as long as possible.

For a beginner, regardless of the ability of the red dot, continuously moving on the wall for 10 minutes may seem impossible, even on a vertical block problem of 5.6 or V0. If this happens to you, try sets of 5 minutes on, 5 minutes off, aiming for a total time on the wall of 30-45 minutes per session. Next session, try 10 minutes of walking, 10 minutes of rest, and so on. Advanced climbers may need to start as low as beginners if they have never done local endurance training, but all climbers should progress quickly.


Do two to four ARC sets each week of ARC training (up to about 4 weeks) or mix one session per week with other training. ARC training is very low intensity, so it can be done often without stressing your muscles and joints. In fact, ARC training can be a great way to actively recover the day after a more intense workout. The next time you have a longer break from climbing, do a few weeks of local endurance training to get you back on track. This will work on technique and establish a good foundation in your climbing from which you can build.

To mix together

ARC training is one of the best ways to train local endurance, but it can be boring to stay on the wall, shooting easy move after easy move, for half an hour. Mix up your ARC routine by trying these ideas:

  • Do technical exercises. Pick a technique like drop knees and do as much of it as you can for five minutes. Choose another technique, such as flagging, for the next five minutes. Also practice these techniques on the way down.
  • Focus on body position. Can you bring your hips closer together or rotate them differently? Do you need both feet for this move? Could you use a lower foot and cross instead?
  • Find as many ways as possible to switch from one take to another – which was the best and why?
  • Focus on your breathing. Keep a steady breathing pattern, but mix in one or two harder strokes every few minutes with strong, focused exhales.
  • If you find high reps boring, even with technical drills, there are other ways to get the benefits of ARC by climbing with a partner or mimicking ARC-style training outdoors. Any exercise that focuses on volume and not climbing difficulty will help.
  • Try to climb any rocks in the gym that are at or below a certain level, like V1 or V0, taking short breaks between problems to avoid getting pumped. Ascend and then descend for an additional mile, resting if necessary. You won’t get the benefits of ARC if you get too pumped up, but the more continuous time you spend on the wall the better. Or climb any toprope routes in the gym that feel moderate and don’t pump you. Alternate routes in your gym with a partner, only stopping to change belays between routes.
  • If you prefer to practice outdoors, grab a partner and climb pitches that are at least one grade below your sight level. Try to climb two to three lengths at a time back to back, then swap with your partner. In a day on the cliff, aim for at least 10 pitches. You should not feel a strong pump at any time. Lower a note or two if you do, especially towards the end of a session. Think of it as a slightly more intense, all-day warm-up, after which you go home.
  • You can use one round of a shorter ARC session as a warm-up for any climbing or training session.

To improve your climbing by learning the right ways to train your weaknesses, check out the rest of our series Learn to Train: A Complete Guide to Climbing Training.