Oxygenation time course and neuromuscular fatigue during repeated cycling sprints with bilateral blood flow restriction

Abstract

The aim was to evaluate changes in peripheral and cerebral oxygenation, cardiorespiratory, and performance differences, as well as neuromuscular fatigue across multiple levels of blood flow restriction (BFR) during a repeated cycling sprint test to exhaustion (RST). Participants performed three RST (10‐sec maximal sprints with 20‐sec recovery until exhaustion) with measurements of power output and V̇O2peak as well as oxygenation (near‐infrared spectroscopy) of the vastus lateralis and prefrontal cortex. Neuromuscular fatigue was assessed by femoral nerve stimulation to evoke the vastus lateralis. Tests were conducted with proximal lower limb bilateral vascular occlusion at 0%, 45%, and 60% of resting pulse elimination pressure. Total work decreased with BFR (52.5 ± 22.9% at 45%, 68.6 ± 32.6% at 60%, P < 0.01 compared with 0%) as V̇O2peak (12.6 ± 9.3% at 45%, 18.2 ± 7.2% at 60%, compared with 0%, P < 0.01). Decreased changes in muscle deoxyhemoglobin (∆[HHb]) during sprints were demonstrated at 60% compared to 0% (P < 0.001). Changes in total hemoglobin concentrations (∆[tHb]) increased at both 45% and 60% compared with 0% (P < 0.001). Cerebral ∆[tHb] increased toward exhaustion (P < 0.05). Maximal voluntary contraction (MVC), voluntary activation level (VAL), and root mean square (RMS)/M‐wave ratio decreased at 60% compared with 0% (P < 0.001, all). MVC and VAL decreased between 45% and 60% (P < 0.05, both). The application of BFR during RST induced greater changes in tissue perfusion (via blood volume, ∆[tHb]) suggesting a possible stimulus for vascular blood flow regulation. Additionally, high‐intensity sprint exercise with partial ischemia may challenge cerebral blood flow regulation and influence local fatigue development due to protection of cerebral function.

Vascular and oxygenation responses of local ischemia and systemic hypoxia during arm cycling repeated sprints

“…As previous research has demonstrated, these hypoxia and BFR conditions induce large increases in deoxygenation of the legs (probably due to a large amount of active muscle mass). 2,22 Additionally, it has been shown that legs are quite responsive (greater changes in perfusion) during systemic hypoxia 22 and BFR conditions, 2 as is substantially confirmed to a greater extent in the present study of the arms. Collectively, this demonstrates that there are differing vascular properties and responses between limbs.…”

“…After critical assessment of number of sprints, power output, torque factor, pedaling frequency, and perceived effort during piloting sessions with arm cycling and RST, the percentage for BFR and resistance for arms were chosen. 2 During familiarization, anthropometric data were measured and the informed consent and health questionnaire [Physical Activity Readiness Questionnaire, PAR-Q & YOU, 13 were completed. Participants donned the BFR cuff (custom-made 4 x 70 cm cuff, 3 × 41 bladder; D.E.…”

“…NIRS measurements and analysis of peripheral oxygenation of the biceps brachii (PortaMonArtinis, Zetten, The Netherlands) were performed similarly as in Willis et al 2 Signals were recorded at 10 Hz and exported (Oxysoft 3.0.53, Artinis, The Netherlands), and application of a 4 th -order low-pass zero-phase Butterworth filter (cutoff frequency of 0.2 Hz) was used to reduce artifacts and smooth perturbations in the signal from pedaling strokes. 15 For each sprint, the maximum and minimum were detected automatically using the rapidly changing increase in deoxyhemoglobin as the visual parameter to confirm the starting point of the test.…”

“…repeated sprint leg cycling test to exhaustion found greater changes in tissue perfusion in blood flow restriction (BFR) conditions and thus suggested a possible stimulus for vascular regulation. 2 With high-intensity leg cycling exercise in systemic hypoxia (repeated sprint training in hypoxia, RSH), which has been shown to acutely reduce blood flow and vasodilation compared to normoxia, 3 training adaptation consists of greater perfusion in active muscles and improved vascular conductance. 4 As modeled by di Prampero, 5 the determining factors of V.O 2max and hemodynamic regulation are dependent on muscle mass.…”

Blood-Flow Restricted Warm-Up Alters Muscle Hemodynamics and Oxygenation during Repeated Sprints in American Football Players

“…Yanagisawa and Fukutani demonstrated that the total hemoglobin/myoglobin concentration significantly increases during exercise with BFR [36], likely because of the impeded venous outflow. Along this line of reasoning, Willis and colleagues reported greater positive changes in tissue perfusion (via blood volume, Δ [THb]) during repeated cycling sprints with BFR compared to non-restricted repeated sprints [46]. Performing BFR during exercise also appears to affect muscle oxygenation.…”