Soft belaying reduces impact without risking the ground. Body and sensor-hand dynamics explained, and when which method belongs in a course.
Belaying dynamically means: you do not just hold a lead fall, you catch it softly so the climber does not slam into the wall. The honest answer to "Isn't soft always better?": no. Soft works only as long as there is no ground or collision risk. Close to the ground you should brake "appropriately short" rather than too dynamically [1].
The problem you want to solve is in the DAV statistics. Belaying too hard with a semi-automatic device can lead to impact injuries, for example on the sensitive ankle [1]. An example from 2018: fall while clipping the 6th quickdraw, hard impact, belayed too hard, shinbone broken [2]. In 2022 a climber slammed into the wall feet first just below the lower-off because the slightly heavier belayer first stepped back: broken lower leg [3].
The counterpart: anyone who belays too softly risks the ground. In a 2022 case (planned fall training) a belayer paid out rope because he thought the climber wanted to clip the 7th quickdraw. The climber jumped into the rope and fell to the ground, comminuted fractures in both heels [3].
Soft belaying is not a comfort feature but a balancing act between wall impact and ground fall.
Entry criteria (practice standard and DAV note):
The DAV distinguishes clearly: as long as there is ground-fall or collision risk, in the gym up to the 4th to 6th quickdraw, no slack may be in play, and the fall should be braked rather short than dynamically [1]. Soft belaying is a skill for mid-wall and above, not for the first quickdraws.
Milestone: In the course you say up to which quickdraw you do not belay dynamically under the DAV rule.
The starting position is the same as for good belaying: at most one metre outside the fall line of the first protection, ready to react in a slight stride, at right angles to the wall. The device hangs at about navel height, brake hand on the brake strand, guide hand just above the device [1]. Beyond ground-fall danger 20 to 50 centimetres of slack are usual [4].
Milestone: You stand in the position in the course and your coach finds nothing to correct.
With semi-automatic devices "soft" does not happen through the device but through your body: from the stride you let the fall load pull you upwards and actively support the movement [1]. That only works well when the partners are about equally heavy. With clearly lighter climbers good body-dynamic belaying becomes extremely demanding to teach and practise, from about 20 kg difference it is hardly achievable well [1].
Milestone: In the course you hold several falls of an equally heavy partner and go with the pull.
Friction in the rope path makes the leader "lighter" from the belayer's point of view. That can be a zigzag line of quickdraws, a roof edge, a thick rough rope or a friction device [1]. If the rope is pulled around two corners and over a roof edge, even with a 90 kg leader not enough pull arrives for body dynamics to work, and the fall becomes hard [1].
Milestone: You explain how, on two different routes, you judge how much pull arrives at you.
The DAV took up sensor-hand dynamics as a research topic in 2017 and tried it in coach training (status of the article: 2018). Here you hold any slack not between guide hand and climber but between guide hand and device: it is a "first braking stage", followed by body dynamics. The method only makes sense if you can hold the leader with the sensor hand alone, and with low friction the effective upper limit is about 60 kg leader weight [1]. It is only allowed once a ground fall or impact on an obstacle can be ruled out [1].
Milestone: You explain why the sensor loop must never be longer than your arm: otherwise burns or shoulder injuries threaten [1].
The most important thing first: holding safely always ranks above softness. Semi-automatic devices have a higher safety reserve when operated correctly, which is why the DAV has recommended them since 2015 as the primary device for sport climbing [1]. If you have to choose between soft and safe holding, choose safe holding.
Before every lead, ask yourself two questions: "How much friction does this rope have?" and "How far is it to the last piece of protection?" Anyone who estimates both in advance does not decide only during the fall whether to go with it or hold back. That is course practice and follows the DAV logic that friction and fall energy must be recognised continuously [1].
You catch a lead fall so that the force acts on harness and climber delayed and reduced. That makes the impact on the wall milder [1].
With body dynamics: from the stride you let the fall load pull you upwards and actively support the movement. That works well with similar weight [1]. Practising belongs in the course.
Not close to the ground; in the gym, according to the DAV, not with slack up to the 4th to 6th quickdraw [1]. And only once you hold falls safely: sensor-hand dynamics is, according to the DAV, intended for Advanced level at the earliest [1].
A DAV method in which the slack is held between guide hand and belay device. It serves as the first braking stage, followed by body dynamics [1].
Because you give rope into the system that the climber lacks when the ground is near. One documented case ended with comminuted fractures of both heels [3].
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