Density Hangs: What They Are and Do They Work
Density hangs are long hangs, about 20 to 40 seconds, on an edge small enough that you reach failure in that window. The idea comes from coach Tyler Nelson, and it claims to thicken tendons. Evidence level: low. No trial in climbers has tested density hangs, and the tendon theory rests on other muscles and on coaching experience.
What are density hangs?
A density hang is a two-arm hang of roughly 20 to 40 seconds, taken to muscular failure. Tyler Nelson of Camp4 Human Performance describes them in his “simplest” finger program (coach source, secondary). The intensity comes from the edge, not from added weight: a jug or a large pocket for beginners, a 10 to 15 mm edge for experts. When you can hit about 30 seconds easily, you move to a smaller edge.
Nelson suggests two days a week for beginners and three for experts, at least 4 to 6 hours away from climbing. His article gives no sets or rest times, so those below are our suggestion, not his.
Do density hangs thicken your tendons?
Nobody has shown it in climbers. Nelson’s explanation is that long, slow loading makes tendon fibres slide and break old bonds, and that rest and food then let denser bonds form. In a separate section on blood flow, he adds that efforts above roughly 30 to 50% can compress the forearm’s blood vessels, which may improve oxygen use over time; he does not tie that directly to density hangs. These are mechanisms proposed by a coach.
The closest research is not on fingers. In a 2001 study, eight young men trained each leg with a different isometric protocol at 70% of maximum: 1-second contractions on one leg, 20-second contractions on the other, with the same total volume. Both legs gained about 32 to 34% in strength, but tendon stiffness rose only with the long contractions. That is a small study on the thigh, and stiffness is not density or injury resistance.
Do they build strength?
Probably not as well as heavy work, though this is our reading, not a tested result. In a 4-week trial of 54 climbers (14 per training group plus a control group), maximal 6-second pulls raised finger strength by 14.3% and hangs at 80% of maximum by 12.4%. Nobody has tested a 30-second hang to failure against these.
How do they compare with max hangs and repeaters?
| Max hangs | Repeaters | Density hangs | |
|---|---|---|---|
| Hang | About 10 s | 7 s on, 3 s off, 6 reps | 20 to 40 s, one go |
| Load | Near maximal | 40 to 80% of max | Moderate, to failure |
| Main target | Maximal strength | Endurance, some strength | Tendon (theory), local endurance |
| Evidence in climbers | Several trials | Several trials | None direct |
See max hangs for the best-studied protocol and repeaters for intermittent work. For the effect of hang length in general, read how long to hang.
How do you do density hangs?
Use them as a small add-on after a proper warm-up, not as your main strength work.
| Parameter | Setting |
|---|---|
| Grip | Open hand or half crimp, same every session |
| Edge | Chosen so failure comes at 20 to 40 s; larger if you drop before 20 s |
| Hang | Two arms, to failure (Nelson); keep the shoulders engaged |
| Sets | 2 to 3 (our suggestion) |
| Rest | 3 minutes (our suggestion, as for max hangs) |
| Frequency | 2 sessions a week, at least 48 hours apart |
| Block | 4 to 6 weeks, then retest your maximum |
Progress by hanging longer on the same edge. Once 30 seconds feels easy, take the next smaller edge. Keep climbing and hard finger days in mind: a long hang to failure still loads the pulleys.
If you want daily, gentler tendon work instead, see daily low-intensity hangs, which rests on tendon research by Keith Baar and on a 2024 study of 526 climbers.
Who should not do this
- Climbers with finger, pulley or tendon pain. Pain stops the session.
- Beginners with under a year or two of regular climbing: climbing itself is enough load.
- Anyone still growing. Young climbers should hangboard only with a coach or sports physician.
- Anyone returning from a finger injury, unless a physiotherapist set the loads.
Stop the hang if you feel a sharp pain, a pop, or pain at the base of a finger that is still there next day. If it persists, see a physiotherapist. Because the hang goes to failure, step off before your grip opens up, and never drop onto your fingers.
Do this in Entralpi
Density hangs depend on picking the right edge, and a hang to failure hides how much force you still hold. In the app, the max strength test measures your maximum; type it in Settings (Profile, then Settings, under Physical Profile, Max strength), then follow a plan or build your own workout with long holds at a share of that maximum. Without the plate, the timer counts the hang for you.
Sources
- Nelson T. The “Simplest” Finger Training Program for Climbers. Camp4 Human Performance (coach source, secondary; cites reviews by Oranchuk, Kubo, and Lum and Barbosa without tying them to density hangs).
- Kubo K, Kanehisa H, Fukunaga T (2001). Effects of different duration isometric contractions on tendon elasticity in human quadriceps muscles. Journal of Physiology, 536(2).
- Devise M, et al. (2022). Effects of different hangboard training intensities on finger grip strength, stamina, and endurance. Frontiers in Sports and Active Living.
- Baar K (2017). Minimizing injury and maximizing return to play: lessons from engineered ligaments. Sports Medicine.
- Gilmore NK, et al. (2024). Effects of different loading programs on finger strength in rock climbers. Sports Medicine – Open.
