Effect of Running-Induced Fatigue on Tibial Acceleration and the Role of Lower Limb Muscle Strength, Power, and Endurance

Abstract

Background: Highimpact loads have been linked with running injuries. Fatigue has been proposed to increase impact loads, but this relationship has not been rigorously examined, including the associated role of muscle strength, power, and endurance. Purpose: This study aimed to investigate the effect of fatigue on impact loading in runners and the role of muscle function in mediating changes in impact loading with fatigue. Methods: Twenty-eight trained endurance runners performed a fixed-intensity time to exhaustion test at 85% of VO 2max . Tibial accelerations were measured using leg-mounted inertial measurement units and sampled every minute until volitional exhaustion. Tests of lower limb muscle strength, power, and endurance included maximal isometric strength (soleus, knee extensors, and knee flexors), single leg hop for distance, and the one leg rise test. Changes in peak tibial acceleration (PTA, g) were compared between time points throughout the run (0%, 25%, 50%, 75%, and 100%). Associations between the change in PTA and lower limb muscle function tests were assessed (Spearman's rho [r s ]). Results: PTA increased over the duration of the fatiguing run. Compared with baseline (0%) (mean ± SD, 9.1g ± 1.6g), there was a significant increase at 75% (9.9g ± 1.7g, P = 0.001) and 100% (10.1g ± 1.8g, P < 0.001), with no change at 25% (9.6g ± 1.6g, P = 0.142) or 50% (9.7g ± 1.7g, P = 0.053). Relationships between change in PTA and muscle function tests were weak and not statistically significant (r s = −0.153 to 0.142, all P > 0.05). Conclusions: Peak axial tibial acceleration increased throughout a fixed-intensity run to exhaustion. The change in PTA was not related to performance in lower limb muscle function tests.

In Deep Water: A Case Study on Kinematics in Deep Water Running

“…While the reasons for this increase are not fully understood, the authors speculate that this was also linked to the onset of fatigue which subsequently produced increased movement of the tibia. This aligns with previous research that has shown that peak tibial acceleration increased over the duration of a fatiguing run 10 . Despite the obvious differences in mechanical loading, specifically the axial loads experienced when running on dryland compared to DWR, the relationship between tibia acceleration in the two conflicting settings is an area for future investigation.…”

Accelerometer-Derived Intensity Thresholds Are Equivalent to Standard Ventilatory Thresholds in Incremental Running Exercise

“…However, accelerometer data are suggested to provide more individualized information. It was already shown that tibial acceleration is modified by running speed [ 18 ] and changed with increasing duration during running with constant speed [ 19 ]. Faster running speeds were associated with increased tibial acceleration, irrespective of running surface, footwear, running experience, or whether the velocity was fixed or self-selected [ 18 ].…”