Related Experiment Video
Updated: Aug 30, 2026

Using Near-Infrared Spectroscopy Wearable Devices to Identify Central Versus Peripheral Limitations During Exercise
Published on: December 19, 2024
Kinematic changes at intensities proximal to onset of lactate accumulation
J Shim1, E O Acevedo, R R Kraemer
1Department of Health, Human Performance, and Recreation, Waco, Texas, Baylor University, Waco, TX 76798, USA. koe_shim@baylor.edu
Aim:
The purpose of this study was to examine changes in selected kinematic variables at 3 running intensities proximal to the onset of blood lactate accumulation (OBLA; 4 mM of blood lactate). It was hypothesized that greater changes in lower body mechanics would occur when running faster than normal race pace compared to when running slower than race pace.
Methods:
Nine competitive male distance runners ran at 3 running intensities (RI): 1) each runner's VO(2) at 10% below the VO(2) at OBLA, 2) VO(2) at OBLA, and 3) VO(2) at 10% above the VO(2) at OBLA. Selected kinematic and physiological variables were measured at each RI.
Results:
VO(2) at RI 1, 2 and 3 was highly correlated with running speed (r=0.93). The blood lactate (BL) showed a nonlinear increase from RI 1 (2.9+/-0.8 mM) to 2 (4.1+/-0.9 mM) to 3 (6.7+/-1.8 mM). The vertical oscillation of center of gravity (VOCOG), stride frequency (SF), range of motion (ROM) of trunk angle, and maximal knee flexion during flight phase (MKFF) changed nonlinearly as did the BL. Significant relationships between BL and VOCOG (r=0.44) and between BL and SF (r=0.51) were found (ps<0.05).
Conclusion:
The findings show a possibility that lower body running mechanics have a relationship with BL.
Related Concept Videos
Muscle Recovery and Fatigue
Alterations in Muscle Tone ll
Isotonic and Isometric Muscle Contractions
Isotonic contractions
Isotonic contractions occur when a muscle changes length while the...
Energy Supply for Muscle Contraction
Muscle Stimulation Frequency
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Excitation-Contraction Coupling in Skeletal Muscles
When an action potential...

