A knee bar is a resting and locking technique where you wedge your leg between two opposing surfaces — jamming the knee or thigh against one and the foot against the other — so the leg supports your weight and frees your hands. A good knee bar can offer a precious no-hands rest on steep terrain.
Spotting is the technique of guiding a falling boulderer to help them land safely on the crash pads, protecting their head and steering their body upright rather than trying to catch their full weight. A spotter stands ready with hands up, and good spotting is a key safety practice in bouldering, where there is no rope.
A whipper is climbing slang for a big, dramatic lead fall — a long, often swinging plunge taken when leading above your protection. Whippers are a normal part of pushing your limit on safe, well-protected sport routes, where the dynamic rope and an attentive belayer turn them into a relatively harmless, if thrilling, experience.
Barn-dooring is when a climber's body swings uncontrollably away from the wall like a door on a hinge, because their weight isn't balanced over their points of contact. It typically happens when the useful holds are all on one side of the body, and is corrected with techniques like flagging to counterbalance.
Being 'pumped' is the burning, swollen feeling in the forearms when they fatigue from gripping, as metabolic by-products and blood build up faster than they clear. A pumped climber loses grip strength and may be unable to hold on, so managing the pump — through rests, efficient movement, and shaking out — is central to endurance climbing.
A lock-off is a technique where you pull a hold in toward your body and hold your bent arm in a static, locked position, freeing the other hand to reach the next hold. Locking off requires pulling strength and good body position, and lets climbers make controlled, static moves instead of dynamic ones.
The quad is an anchor rigging method that uses a doubled loop of cord or sling clipped across two points, with two strands isolated by limiter knots to form a master point. It equalizes well between the points, adjusts to moderate changes in load direction, and stays redundant if one strand is cut — making it a popular modern two-bolt anchor.
The sliding X is a self-equalizing anchor rigging method where a sling is clipped between two points with a twist in one strand, letting the master point slide to follow the direction of pull. It adapts to changing load directions but can extend and shock-load the remaining point if one fails, so it is used carefully, often with limiter knots.
The master point is the single, strong, central point of a climbing anchor where all the individual pieces are brought together and equalized. The belay device, the climber's tether, and the rope all clip into the master point, keeping the anchor simple, redundant, and easy to check. It is also called the power point.
A ground fall, also called 'decking', is when a climber falls all the way to the ground — the most dangerous kind of climbing fall. The risk is highest low on a route before much protection is placed, and when there's excess slack in the system. Avoiding ground falls drives many belaying and protection habits, like clipping early and spotting boulderers.