Jogging

The repercussions of FHL when walking are even more pronounced when running. The impact on the ground is more pronounced and induces more stress on the joints, particularly on the knee and lower back. This deferral depends on the position of the body at the moment of impact. However, we have seen that FHL shifts in time from pronation to supination and vice versa. The body is therefore not ideally positioned for the attack of the heel and the musculature is not in a position to absorb the stresses in an optimal way either. It is also known that the bending moment is increased and this has repercussions on the lumbopelvic hinge with the projection of the upper body forward. Stabilization is achieved at the cost of significant muscular effort, which can be a source of lower back pain (overload of the erectors of the trunk). The "runner's knee" or iliotibial friction syndrome illustrates the remote repercussion of FHL (video).

Pivot or pivot-contact sports

Pivot sports include activities such as tennis, volleyball, skiing, dance, badminton, gymnastics, etc. Pivot-contact sports include rugby, soccer, basketball, handball and combat sports. These sports are known to be at the risk of severe knee sprains. What they all have in common is the pivotal movement that occurs when changing direction while running, dribbling or landing on a jump. This pivot movement can be brutal when the foot suddenly pronates and drags the knee into a downward spiral of valgus-internal tibial rotation, the "medial collapse" of the knee (see video). This mechanism is at the origin of most tears of the knee’s anterior cruciate ligament. The starting point of this sudden pronation of the foot is a characteristic of FHL that we have highlighted by analyzing the footprint on the ground during our connected treadmill assessments.

Golf

The reproducibility of the sporting gesture is a key element to progress in certain sports such as golf or tennis. However, this quality depends to a large extent on the stability of both anchoring to the ground and alignment of the upper body. We can study this balance by projecting the instantaneous center of gravity via a loading platform. In the presence of FHL, we see that this projection tends to shift backwards and outwards, and can therefore disturb balance. Improving footwear with new concept supports seems to have a promising effect.

Skiing

You might think that keeping the foot in the ski-shoe prevents medial collapse and protects the knee, but this is not the case. The protective effect plays out at the beginning but quickly the foot is "released" in pronation, especially since the rear tongue of the shoe keeps the ankle in plantar flexion. The forces involved are unequal and that is why severe knee sprains are so common in skiing.