Influence of blood flow occlusion on the development of peripheral and central fatigue during small muscle mass handgrip exercise

Abstract

Key pointsr Critical power represents an important threshold for neuromuscular fatigue development and may, therefore, dictate intensities for which exercise tolerance is determined by the magnitude of fatigue accrued.r Peripheral fatigue appears to be constant across O 2 delivery conditions for large muscle mass exercise, but this consistency is equivocal for smaller muscle mass exercise.r We sought to determine the influence of blood flow occlusion during handgrip exercise on neuromuscular fatigue development and to examine the relationship between neuromuscular fatigue development and W .r Blood flow occlusion influenced the development of both peripheral and central fatigue, thus providing further evidence that the magnitude of peripheral fatigue is not constant across O 2 delivery conditions for small muscle mass exercise.r W appears to be related to the magnitude of fatigue accrued during exercise, which may explain the reported consistency of intramuscular metabolic perturbations and work performed for severe-intensity exercise.Abstract The influence of the muscle metabolic milieu on peripheral and central fatigue is currently unclear. Moreover, the relationships between peripheral and central fatigue and the curvature constant (W ) have not been investigated. Six men (age: 25 ± 4 years, body mass: 82 ± 10 kg, height: 179 ± 4 cm) completed four constant power handgrip tests to exhaustion under conditions of control exercise (Con), blood flow occlusion exercise (Occ), Con with 5 min post-exercise blood flow occlusion (Con + Occ), and Occ with 5 min post-exercise blood flow occlusion (Occ + Occ). Neuromuscular fatigue measurements and W were obtained for each subject. Each trial resulted in significant peripheral and central fatigue. Significantly greater peripheral (79.7 ± 5.1% vs. 22.7 ± 6.0%) and central (42.6 ± 3.9% vs. 4.9 ± 2.0%) fatigue occurred for Occ than for Con. In addition, significantly greater peripheral (83.0 ± 4.2% vs. 69.0 ± 6.2%) and central (65.5 ± 14.6% vs. 18.6 ± 4.1%) fatigue occurred for Occ + Occ than for Con + Occ. W was significantly related to the magnitude of global (r = 0.91) and peripheral (r = 0.83) fatigue. The current findings demonstrate that blood flow occlusion exacerbated the development of both peripheral and central fatigue and that post-exercise blood flow occlusion prevented the recovery of both peripheral and central fatigue. Moreover, the current findings suggest that W may be determined by the magnitude of fatigue accrued during exercise.

Influence of group III/IV muscle afferents on small muscle mass exercise performance: a bioenergetics perspective

“…Cumulating evidence supports the concept that group III/IV muscle afferents are critically involved in determining the curvature constant of the force–duration relationship (Broxterman et al . ; Hureau et al . ).…”

Critical Power

“…29). While, in any form of exercise, CP likely reflects the limit of force or power demands that result in the progressive accumulation of fatigue during >CP exercise (15,16,18,48), it is the W′ parameter that provides us the clearest insight into the dynamics of the mechanisms that cause fatigue and its progression to eventual intolerance.…”

“…Therefore, it is likely an oversimplification to assume, for example, that W′ reflects a cytosolic depletion of PCr or accumulation of Pi or H + . Broxterman et al (15) directly addressed this issue using rhythmic handgrip exercise and surface electrical stimulation of the flexor digitorum superficialis superimposed on the MVC to assess the contributions of central and peripheral fatigue to exercise intolerance. They found a significant inverse correlation between both the decline in MVC and peripheral fatigue (the decline in potentiated doublet twitch force) and W′.…”

The effect of resting blood flow occlusion on exercise tolerance and W′

“…The mechanisms determining W= are associated with the depletion of intramuscular energy stores [e.g., phosphocreatine (PCr), glycogen, and O 2 stores] (17, 19 -21) and the accumulation of fatigue-inducing metabolites [e.g., inorganic phosphate (Pi) and hydrogen ions (H ϩ )] (5, 10, 13, 17). Thus, the magnitude of the W= is related to factors that may constrain or arise from these alterations in the myofiber milieu, such as the breadth of the severe intensity domain, the magnitude of the oxygen uptake slow component, and the development of fatigue (3,4,23,30,31 [PCr] depletion for the same duration of resting blood flow occlusion. These findings suggest that resting metabolism is maintained via aerobic energy production utilizing tissue oxygen stores over the initial several minutes of resting blood flow occlusion, after which resting metabolism must be maintained via supplemental anaerobic energy production.…”

“…The mechanisms determining W= are associated with the depletion of intramuscular energy stores [e.g., phosphocreatine (PCr), glycogen, and O 2 stores] (17, 19 -21) and the accumulation of fatigue-inducing metabolites [e.g., inorganic phosphate (Pi) and hydrogen ions (H ϩ )] (5,10,13,17). Thus, the magnitude of the W= is related to factors that may constrain or arise from these alterations in the myofiber milieu, such as the breadth of the severe intensity domain, the magnitude of the oxygen uptake slow component, and the development of fatigue (3,4,23,30,31).…”