The effects of athletic training with minimal footwear on toe flexor muscle strength

Forty-seven female sport students participated and were randomly divided in three groups: The experimental group (EG; n=18; 25±5 yrs, 59±6 kg) and the training control group (TG; n=18; 23±2 yrs, 64±6 kg) performed high intensity athletic training (3 weeks, 5 times per week, 30 min per session) on the forefoot. EG wore a minimal shoe, TG performed the exercises with traditional training shoes. The basic control group (CG; n=11; 27±5 yrs, 63±7 kg) participated in no training program. To evaluate the training effects on TFM strength, maximum metatarsal phalangeal joint (MPJ) plantar flexion moments during maximal voluntary isometric contractions (MVIC) at 0° and 25° MPJ dorsal flexion were measured in a custom made dynamometer before and after the training intervention.

The results showed that (1) in 0° MPJ dorsal flexion, MPJ moments were significantly increased in EG (P <0.01) and TG (P <0.05) and differed significantly to CG (P <0.05); (2) in 25° MPJ dorsal flexion, TFM strength was significantly increased in EG (P <0.01), but not in TG and CG (P > 0.05). In this joint angle position EG significantly differed to TG and CG (P <0.05). The results of the study show that athletic exercises with minimal footwear strengthen TFM after three weeks intensive training.