Learn the knee swing-down and swing-up on the bar: knee hang, swinging, active free leg, spotter on the swing-leg side and errors that cost the straddle sit.
In the knee swing-up you hang upside down from the bar with one knee hooked in, swing forward and back, and get back into the straddle sit on the bar through the swing of the free leg. With it you practise the feeling of hanging upside down on the bar without your hands being the only connection.
The honest answer to "How hard is it?": The knee swing-down part feels brave, the swing-up is then a timing puzzle. BASPO describes it this way: from the straddle sit with overgrip, lift the body, push it back and hook the knee, swing forward and back in the knee hang and return to the straddle sit [1]. At the turning point of the swing the straight rear leg actively kicks back, and the front leg presses on the bar [2].
A classification: in the Swiss upper-secondary test (uneven bars) the "knee swing-up with change of grip" is among the difficult connecting elements [3]. The simple form we practise here is a basic element in school gymnastics [2], but not trivial.
Hands take the rail in overgrip, you hook one leg in at the back of the knee. With a light swing forward and back you climb onto the rail into the sit [2]. Milestone: You hang calmly in the knee hang for five seconds with straight arms.
The free, straight leg provides the swing, the arms are always straight [1]. Milestone: five swings forward and back, arms stay straight.
From the straddle sit shift your weight back, the body swings back-down, the rear leg stays straight, the front leg bends so the rail slides into the back of the knee [2]. The swing runs to the end and is braked [1]. Milestone: three controlled swing-downs with a spotter.
In the swing-up the free, straight leg gives the impulse, the heel goes actively back-up [1]. Then you reduce the arm-trunk angle and arrive in the straddle sit [2]. Milestone: three swing-ups with push help at the upper back and thigh [1].
The rhythm stays the same, the upper body is straight, the arms long [2]. When the vertical is reached, the hands stay put and the body swings on [1]. Milestone: three repetitions in a row, you end in the straddle sit.
Clamp a sock between chin and chest. It forces you into the C+ posture and gives honest feedback: if it falls out, you took your head back [1]. The Swiss material uses exactly this trick against the head-back problem.
The hip pull-over (Felgaufschwung) takes you from standing into support on the bar. The knee swing-up leads from the knee hang back to the straddle sit [1][2]. Both end on the bar, but with a different starting point and a different rotation.
The pressure is normal, especially without long trousers. If it stabs or your toes tingle, you stop (practice). With a bit of practice you get used to the feeling.
Yes, at the beginning. The spotters stand on the swing-leg side and push at the thigh and lower back [2]. Later a light safeguard is enough.
In the Swiss upper-secondary test, "knee swing-up with change of grip" is among the difficult connecting elements on the uneven bars [3]. The simple variant counts as a basic element in school gymnastics [2].
That is an experience-based estimate: with help many manage the first swing-up after a few sessions, without help it takes longer. There is no study figure for this.
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