Most climbers think intensity is the main danger in finger training.
It isn’t.
The biggest hidden risk — and the biggest source of progress — is joint angle stability.
Tendon loading changes dramatically depending on how the finger joints are positioned.
Two hangs with the same weight can stress the tendon completely differently simply because one joint shifts by a few degrees.
Understanding grip position is not optional.
It is the foundation of safe loading.
1. Finger training is not about “grip type” — it’s about joint angles
Climbers talk about:
- open hand
- half crimp
- full crimp
But these categories are too coarse.
What matters is how much you bend:
- the middle finger joint (Proximal Interphalangeal joint — PIP)
- the small fingertip joint (Distal Interphalangeal joint — DIP)
These two angles determine:
- where the force goes
- which pulley gets loaded (A pulley is a small ligament that keeps the flexor tendons close to the bone in your fingers.
When the angle or load becomes too high, a pulley takes sharply increased strain — especially the A2 pulley. (See Anatomy → Finger Structure for a deeper explanation.) - how the tendon handles the tension
Two climbers in the “same” half crimp may load their PIP and DIP totally differently — and therefore load their tendons differently.
2. Small changes in angle = big changes in tendon stress
A 5–10° change in PIP or DIP angle can:
- double local tendon stress
- shift load from A2 → A3 → A4
- change fatigue rate
- increase or decrease strain rate
This is why:
- some hangs feel “sharp”
- some feel “smooth”
- some fatigue fast
- some allow long sets
Same weight.
Different anatomy.
Different joint behavior.
3. The problem: climbers default to compensation
During hard hangs, the body will subconsciously:
- unroll the fingers
- tighten the thumb
- flex the wrist
- rotate the shoulder
All to maintain force output.
These compensations make the rep look “strong,” but the tendon sees:
- shifting angles
- unstable loading
- unpredictable strain
- Compensations hide overload.
Stable joint angles reveal it.
4. A stable grip is more important than a heavy load
The optimal grip for training is:
- mechanically stable
- easy to repeat
- consistent across reps
- joint angles don’t drift
- feels predictable
- tendon strain feels “diffuse,” not sharp
This grip is YOUR personal baseline.
For most climbers:
- full crimp = too extreme for training volume
- open hand = too passive
- half crimp (with slight variance) = most stable zone
- But the best grip is the one you can hold without angle drift.
5. How to find your stable training grip
Use this quick check:
1) Position
Get into your usual grip.
2) Load slightly
Hang with just enough weight to activate tension.
3) Observe angle behavior
- Does the DIP unroll?
- Does the PIP collapse?
- Do you flex the wrist to compensate?
- Do you twist the elbow?
Any drifting = unstable grip.
4) Adjust until stable
Find the joint angle where:
- force feels evenly distributed
- no joint is “taking over”
- nothing shifts when you increase load slightly
This is your training grip, regardless of what it looks like.
6. Stable grip → predictable adaptation
When joint angles stay stable:
- tendon load is consistent
- collagen remodeling becomes efficient
- fatigue patterns become predictable
- risk drops dramatically
- performance stabilizes session to session
When angles drift:
- stress becomes inconsistent
- adaptation breaks
- injury risk rises
- fatigue becomes chaotic
- Stable angles = the missing link in most finger training programs.
Putting it all together
Grip position determines force distribution.
Force distribution determines tendon strain.
Tendon strain determines whether you adapt or overload.
A small angle mistake can defeat:
- good loading
- good volume
- good repeatability
A stable grip amplifies:
- safe intensity
- productive volume
- clean repeatability
- predictable progress
This is the final pillar of the Principles cluster.
What comes next
Now that you understand grip stability and force distribution, we can move to the Application cluster — where the principles translate into structure.
Next article (Application #1):
How to Build a 4-Week Finger Strength Progression (That Respects Tendon Timelines)
This will show how to combine:
- starting load
- consistency tracking
- intensity vs volume balance
- stable grip
… into an actual multi-week block.