Results – Biomechanics

Results biomechanics

The tested running shoe crivit PRO showed similar biomechanical values in comparison to the brand benchmark shoes Asics Nimbus 18 and Nike Pegasus 33 as no difference were observed in the dampening, pronation control, and spatio-temporal parameters. Ground reaction force values (strong indicator of shoe dampening) were considerably low indication a very good impact dampening. Low pronation values indicate good rearfoot stability and demonstrate the good motion control qualities of the crivit PRO shoe.

Das getestete Schuhmodell Crivit Pro 2 zeigten in keinem der biomechanischen Tests signifikante Unterschiede zu den hochpreisigen Markenschuhen. Die beiden Markenschuhmodelle wurden in vielen Vormodellen weiterentwickelt und werden als Benchmark mit hervorragenden biomechanischen Eigenschaften eingeschätzt.

 

Dampening / cushioning

Dampening is one of the key features of running shoes which can determined validly using the biomechanical variable force loading rate (the rate at which force is build up during initial ground contact -> high loading rate = low dampening).

The crivit PRO and the Asics Nimbus 18 showed the lowerst loading rates – to that effect the highest dampening. No differences were observed between the Asics and the crivit PRO, thus, their dampening properties can be considered similar. In contrast, we observed significantly higher force loading rates in the Nike Pegasus 33 compared to the Asics Nimbus (-27%, p<0,001) and the crivit PRO (-20%, p<0,01). The dampening properties of the Nike Pegasus are therefore considered to be the lowest in the test group.

 

Fig 1: Dampening measured as force loading rate [BW/s]. Mean values and 95% confidence intervals.


Pronation

To evaluate the stability property of the shoes two biomechanical parameters were determined: maximum pronation and maximum pronation velocity. Especially pronation velocity is often discussed in the scientific literature as a potential factor in the development of overuse injuries. Generally, the lower the pronation velocity the higher the stabilizing / motion control properties of the shoe. Norm values (highly dependent on the measurement method) for maximum pronation are around 10°, for maximum pronation velocity between 400-700°/s.

Fig 2: Maximum pronation. Lower values represent higher stabilizing / motion control properties of the shoe and are often considered positive. No differences were observed between shoe models.

 

In our test no difference in maximum pronation or maximum pronation velocity were observed between the shoe models. Despite not being classified as motion control shoes, all shoes demonstrated low pronation values at the lower end of the norm ranges, thus, providing a good stabilization.

 

Abbildung 3: Maximum pronation velocity. Lower values represent higher stabilizing / motion control properties of the shoe and are often considered positive. No differences were observed between shoe models.

 


Fußaufsatzwinkel

Foot inclination angle at inital touch down is an indicator of running style, more specifically, whether runners use a fore-, middle- or rearfoot foot strike. About 70% of all runners use a rearfoot strike pattern as their regular running style. However, running shoes with very low dampening often force runners to adapt their running pattern towards a more forefoot foot strike and compensate thereby the low dampening of the shoes with body own dampening mechanisms. This might be problematic because these adapations can cause overloading of structures in the ankle complex, the shank musculature or the knee.

Foot inclination angle of the three tested shoe models were not significantly different. Runners demonstrate in all shoe models a rearfoot striking angle with an inclination angle of 7-9°. These values are considered to be within the norm range of regular rearfoot running.

 

Fig 4: Foot inclination angle at inital ground contact. Positive anlges indicate rearfoot striking. Foot inclination angles did not differ between the tested shoe models.

 


Ground contact time

Ground contact time is the time in ms where the foot is on the ground. Norm values for the tested running speed are within 200-300ms. Changes in these values indicate an adaptation of the running pattern towards a forefoot running stlye.

The observed values were within the norm range and did not differ between the tested shoe models.

Fig 5: Ground contact time [ms]. No difference were observed between the tested shoe models.