Learn the one-foot glide: shift weight onto the glide leg, lift the free leg, glide calmly. Build-up in stages, typical mistakes and what fall data say about balance.
The honest answer up front: gliding on one foot means shifting your weight completely onto one leg, lifting the other briefly and rolling calmly on one skate. It looks like a small thing but is the basis for brakes such as the heel stop or the T-stop and for turns. In the T-stop, the first phase according to the curriculum of the German Inline Skate Teachers Association (DILV) starts with shifting weight onto the glide leg while the braking leg is lifted [1]. In plain words: without a stable standing leg, your braking leg has nothing to work against.
Why balance in particular? In a survey of 313 recreational inline skaters, 32.9% named a spontaneous loss of balance as the cause of involuntary falls, another 17% uneven pavement and 11.3% failing to stop [2]. A review notes that falls mostly arise from loss of balance and that falling skaters put their hands out; about a quarter of all inline skating injuries are wrist fractures [3]. In plain words: if you train your balance, you protect yourself where it hurts.
How hard is it? You understand the principle in a minute. Until you roll calmly on each leg for a few seconds, it takes several sessions, in experience terms. There is no study on this exercise itself. Anything without [n] is practice standard.
Stand in the ready position with slightly bent knees and weight on the balls of the feet [1]. Lift one leg briefly, alternately. The DILV names "alternately lifting one leg" explicitly as a standing exercise [1]. Milestone: stand 10 seconds on each leg without the skate rolling away.
Roll slowly straight ahead. Shift your weight over the glide leg, as in the T-stop: weight shift to the glide leg, lift the other leg [1]. Stay low, knees bent.
Lift the free leg only a few centimeters. Your gaze goes ahead, not at the wheels. The upper body stays calm. Milestone: roll on one foot for 2 seconds, 5 times per side.
Extend the glide phase. The DILV describes the principle for stride 2: few steps, longer gliding, more ground gained [1]. The standing leg stays bent, the weight stays over the middle of the wheels. Milestone: roll 5 seconds on one foot on each side.
Practice one-foot riding in gentle arcs and one-foot slalom around cones, as the DILV names "one-foot riding" and "one-foot slalom" as improvement exercises [1]. That strengthens the feel for the edge. Milestone: you glide on one foot through a wide arc without putting the other foot down.
Film your one-foot glide attempt from the front. Do you see knee, hip and shoulder lined up over the standing foot? Then the balance is stable. If the knee falls inward, practice with a wall for support until the axis sits. And switch standing leg and free leg regularly, otherwise a "good" and a "bad" side develop.
It is the basis for brakes such as the T-stop, in which weight is shifted to the glide leg and the braking leg is lifted [1], and for turns.
As a milestone, 5 seconds per side is enough for a start (practice benchmark). There is no study figure for this.
With an almost straight body a fall backward can easily happen [1]. Bend the knees and shift the weight onto the balls of the feet.
No. DGUV requires complete protective gear in inline skating at all times: helmet, knee, elbow and wrist guards [4].
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