Table 1 Detailed description of the instructions to the participants

Walking

Start in an upright position, with the feet aligned to the marked starting line. Walk at comfortable speed, as you would normally do, to the other side of the lab (10 m) until you have passed the stopping line.

Forward lunge

Start in an upright position, keep your hands slightly away from your body and the toes aligned with the marked starting line. Step forward with your heel over the predetermined distance (70% leg length) as marked on the ground. While stepping forward, bring the weight of your upper body over the leading leg and be sure that the contralateral leg keeps in contact with the floor throughout the forward lunge. Make sure that the entire foot contacts the ground and subsequently step backwards to the initial start position.

Sideward lunge

Start in an upright position, keep your hands slightly away from your body and the side of the foot aligned with the marked starting line. Step sideward with your foot over the predetermined distance (70% leg length) as marked on the ground and keep the foot parallel to the marked line. While stepping sideward, bring the weight of your upper body over the leading leg and be sure that the contralateral leg keeps in contact with the floor throughout the sideward lunge. Make sure that the entire foot makes contact with the ground and subsequently step backwards to the initial start position.

Ascent / Descent stairs

Start in an upright position, with the feet aligned next to each other in front of the first step. Ascent the stairs and wait on top of the staircase until we have given the instruction to turn around. At our command, descent the stairs and wait at the bottom of the stair until you are instructed to turn around.

Single leg squat

Stand still with feet shoulder width apart and put your hands on the pelvis. Shift the weight to one side (i.e. stand on one leg), lift the other foot from the ground. When standing on one leg, squat on the standing leg as deep as possible but remain balanced and make sure the other leg is not contacting the ground. When maximal flexion is reached, extend the knee and when the leg is fully extended, place your other foot down again.

Sit to Stand

Stand with your back towards the stool with the feet shoulder width apart and with the arms hanging alongside of your body. Sit down without looking over your shoulder, remain seated (similar as you would sit on a chair), and stand up again (without swinging your arms). The stool height was pre-set on the participants knee height.