Author(s): BISSAS, A., WALKER, J.2, DE WAAL, S.1, BALAGOPALAN, A.1, HOBBS, S.1, CRONIN, N.1,3, Institution: UNIVERSITY OF GLOUCESTERSHIRE, Country: UNITED KINGDOM, Abstract-ID: 2715

INTRODUCTION:
Carbon-plated “super shoes” improve running economy, yet the mechanisms underpinning these benefits under fatigued conditions remain unclear [1], particularly in female runners. This study examined the effects of carbon-plated versus regular running footwear on running economy (RE), performance, lower leg muscle activation and dynamics before and after a fatiguing run in female amateur road runners.
METHODS:
15 competitive amateur female runners ran on the treadmill at 85% of vVO2 max until exhaustion wearing either a Nike Pegasus (regular shoe: RS) or Nike Alphafly 3 (super shoe: SS). Immediately before and after the fatiguing run, participants ran for 5 min at 70% of vVO2 max where continuous breath-by-breath, EMG and ultrasound (n = 7) data were collected. A Delsys Trigno system recorded (2000 Hz) activity from Lateral Gastrocnemius (GL), Medial Gastrocnemius (GM), Soleus (SOL) and Tibialis Anterior (TA), and a Telemed system recorded (125 Hz) fascicle movement from GL and SOL. RE was calculated as the mean oxygen uptake (ml·kg-1·km-1) over the last 60 s of the collection period. Mean EMG activity – normalised to peak activity detected pre-fatigue – was calculated over a full stride for each muscle, with fascicle range (FR) and velocity (FV) extracted from the ground contact phase. Two-way repeated-measures ANOVA (α = 0.05) tested main and interaction effects.
RESULTS:
Runners ran for longer (55%) in SS than RS (20.52 ± 5.40 min > 13.22 ± 3.68 min, p<0.01). Post VO2 values increased (p<0.01) for both shoes, but overall SS displayed lower VO2 values (p<0.05). GL EMG was higher (p<0.01) in SS across time points (pre and post), with SSpost > RSpost by 40%. Same overall difference between shoes was recorded for TA (p<0.05) but not for GM. SOL activity was not different between shoes, but both displayed higher activity (p<0.05) post-fatigue. FV for GL and SOL and FR for SOL showed no significant changes, with FR for GL decreasing after the run (-10–20%, p<0.01).
CONCLUSION:
Carbon-plated super shoes substantially enhanced endurance performance at a fixed relative intensity, accompanied by lower metabolic cost before and after fatigue. This indicates that footwear influences the physiological cost of running and the way fatigue responses manifest under sustained high-intensity exercise. Super shoes were also associated with altered lower-leg muscle activation patterns, suggesting modified neuromuscular coordination rather than simple reductions in muscular demand. In contrast, muscle fascicle behaviour showed limited shoe-specific differences, warranting cautious interpretation. Together, these findings extend current evidence to competitive amateur female runners and suggest that super shoes may offer performance benefits to under-researched populations during prolonged, fatigue-inducing running conditions beyond short-duration laboratory trials.

REFERENCES:
[1] Hébert-Losier K, Pamment M. Sports Biomech 2023;22(3):335–350.