Article Review



Differences in running biomechanics between a maximal, traditional,and minimal running shoe


Background:


Despite significant innovation in shoe design over this time period, injury rates in runners remained very high. Many shoe companies have recently begun altering the amount of cushioning in their shoes, offering both minimally and maximally cushioned options. Minimal shoes, which have been studied more extensively than their maximal counterparts, are defined by low midsole stack height, low heel-toe drop, high flexibility, and lower weight. While minimal shoes do appear to decrease patellofemoral joint loading compared to a neutral cushioned shoe, calf and achilles tendon loading may increase while wearing minimal shoes. In addition, if runners maintain a rearfoot strike, minimal shoes often increase the average vertical loading rate and vertical impact peak.Greater impact forces and vertical loading rates have been associated with a greater risk of sustaining an overuse injury.

Maximal shoes, while are also generally constructed with a low heel-toe drop, contain substantially greater midsole cushioning from the forefoot to the rearfoot compared to a traditional shoe. At the ankle, while Achilles tendon loads were found to be lower in the maximal shoe compared to a minimal shoe, another study found that runners may display prolonged eversion in maximal shoes, which has been associated with injury both retrospectively and prospectively. At the knee, while patellofemoral forces were not significantly different between a traditional and maximal shoe, these forces were greater in both shoes compared to the minimal shoe. In regards to ground reaction force parameters, while some studies have found no differences between a maximal and traditional shoe for the loading rate or impact peak of the vertical ground reaction force, other studies have found that the loading rate and impact peak are higher in maximal compared to traditional footwear. In addition, two studies have found that the instantaneous loading rate was higher in a minimal shoe compared to a maximal shoe.

This article compares ankle kinematics (dorsiflexion and eversion) and ground reaction forces between a minimal, traditional, and maximal shoe from the same manufacturer where the only difference between shoes is the stack height of the midsole.


Who and How:

Twenty recreational runners ran overground in the laboratory in three shoe conditions (maximal, traditional, minimal) while three-dimensional kinematic and kinetic data were collected using a 3D motion capture system and two embedded force plates.

Kinetic variables of interest included the average vertical loading rate (AVLR), vertical impact peak (VIP), and vertical active peak (VAP) of the ground-reaction force. Kinematic variables of interest included eversion and dorsiflexion angles (angle at initial contact, peak angle, joint excursion, and angle attoe-off), as well as eversion duration.


Results:

Running in a minimal shoe increased the loading rate compared to a maximal shoe, but no other differences were seen in the ground reaction force variables. This finding indicates that differences in ground reaction force variables in previous studies may be due to factors outside of the midsole stack height. Peak eversion was greater in the maximal and minimal shoes, while eversion duration and eversion at toe-off were significantly greater in the maximal shoe. While the eversion mechanics observed in the maximal shoe have been associated with an increased risk of injury, any link between injury and maximal shoe use is purely speculative. Future research needs to consider that not all maximal running shoes will affect biomechanics in the same manner.


Practical implications:

• While the average loading rate was higher in minimal shoes for runners who maintained a rearfoot strike pattern, no other differences were noted between shoes for any ground reaction force variable.

• Previously cited differences in the loading rate or impact peak of the vertical ground reaction force between maximal and traditional shoes may be due to factors outside of the amount of midsole cushioning.

• Participants displayed prolonged eversion duration in the maximal shoe, which may increase injury risk to the shin, calf, and Achilles tendon.


Full Article:

https://www.jsams.org/article/S1440-2440(19)30473-6/pdf

J.J. Hannigan and C.D. Pollard / Journal of Science and Medicine in Sport 23 (2020) 15–19


#Running #Runningshoes #Biomechanics

© 2020 by SPACECLINICS

  • Facebook
  • Twitter
  • LinkedIn