Effects of Active Preconditioning With Local and Systemic Hypoxia on Submaximal Cycling

Author(s):  
Olivier Girard ◽  
Romain Leuenberger ◽  
Sarah J. Willis ◽  
Fabio Borrani ◽  
Grégoire P. Millet

Purpose: The authors compared the effects of active preconditioning with local and systemic hypoxia during submaximal cycling. Methods: On separate visits, 14 active participants completed 4 trials. Each visit was composed of 1 preconditioning phase followed, after 40 minutes of rest, by 3 × 6-minute cycling bouts (intensity = 85% of critical power; rest = 6 min). The preconditioning phase consisted of 4 × 5-minute cycling bouts at 1.5 W·kg−1 (rest = 5 min) in 4 conditions: control (no occlusion and normoxia), blood flow restriction (60% of total occlusion), HYP (systemic hypoxia; inspired fraction of oxygen = 13.6%), and blood flow restriction + HYP (local and systemic hypoxia combined). Results: During the preconditioning phase, there were main effects of both systemic (all P < .014) and local hypoxia (all P ≤ .001) on heart rate, arterial oxygen saturation, leg discomfort, difficulty of breathing, and blood lactate concentration. Cardiorespiratory variables, gross efficiency, energy cost, and energy expenditure during the last minute of 6-minute cycling bouts did not differ between conditions (all P > .105). Conclusion: Local and systemic hypoxic stimuli, or a combination of both, during active preconditioning did not improve physiological responses such as cycling efficiency during subsequent submaximal cycling.

2016 ◽  
Vol 62 (Suppl.1) ◽  
pp. 237-242 ◽  
Author(s):  
TOSHIHARU NATSUME ◽  
HAYAO OZAKI ◽  
TAKASHI NAKAGATA ◽  
SHUICHI MACHIDA ◽  
HISASHI NAITO

2021 ◽  
Vol 1 (5) ◽  
pp. 263502542110326
Author(s):  
Steven R. Dayton ◽  
Simon J. Padanilam ◽  
Tyler C. Sylvester ◽  
Michael J. Boctor ◽  
Vehniah K. Tjong

Background: Blood flow restriction (BFR) training restricts arterial inflow and venous outflow from the extremity and can produce gains in muscle strength at low loads. Low-load training reduces joint stress and decreases cardiovascular risk when compared with high-load training, thus making BFR an excellent option for many patients requiring rehabilitation. Indications: Blood flow restriction has shown clinical benefit in a variety of patient populations including healthy patients as well as those with osteoarthritis, anterior cruciate ligament reconstruction, polymyositis/dermatomyositis, and Achilles tendon rupture. Technique Description: This video demonstrates BFR training in 3 clinical areas: upper extremity resistance training, lower extremity resistance training, and low-intensity cycling. All applications of BFR first require determination of total occlusion pressure. Upper extremity training requires inflating the tourniquet to 50% of total occlusion pressure, while lower extremity exercises use 80% of total occlusion pressure. Low-load resistance training exercises follow a specific repetition scheme: 30 reps followed by a 30-second rest and then 3 sets of 15 reps with 30-seconds rest between each. During cycle training, 80% total occlusion pressure is used as the patient cycles for 15 minutes without rest. Results: Augmenting low-load resistance training with BFR increases muscle strength when compared with low-load resistance alone. In addition, low-load BFR has demonstrated an increase in muscle mass greater than low-load training alone and equivalent to high-load training absent BFR. A systematic review determined the safety of low-load training with BFR is comparable to traditional high-intensity resistance training. The most common adverse effects include exercise intolerance, discomfort, and dull pain which are also frequent in patients undergoing traditional resistance training. Severe adverse effects including deep vein thrombosis, pulmonary embolism, and rhabdomyolysis are exceedingly rare, less than 0.006% according to a national survey. Patients undergoing BFR rehabilitation experience less perceived exertion and demonstrate decreased pain scores compared with high-load resistance training. Conclusion: Blood flow restriction training is an effective alternative to high-load resistance training for patients requiring musculoskeletal rehabilitation for multiple disease processes as well as in the perioperative setting. Blood flow restriction has been shown to be a safe training modality when managed by properly trained physical therapists and athletic trainers.


2021 ◽  
Vol 16 (1) ◽  
pp. 154-157
Author(s):  
Naoya Takei ◽  
Katsuyuki Kakinoki ◽  
Olivier Girard ◽  
Hideo Hatta

Background: Training in hypoxia versus normoxia often induces larger physiological adaptations, while this does not always translate into additional performance benefits. A possible explanation is a reduced oxygen flux, negatively affecting training intensity and/or volume (decreasing training stimulus). Repeated Wingates (RW) in normoxia is an efficient training strategy for improving both physiological parameters and exercise capacity. However, it remains unclear whether the addition of hypoxia has a detrimental effect on RW performance. Purpose: To test the hypothesis that acute moderate hypoxia exposure has no detrimental effect on RW, while both metabolic and perceptual responses would be slightly higher. Methods: On separate days, 7 male university sprinters performed 3 × 30-s Wingate efforts with 4.5-min passive recovery in either hypoxia (FiO2: 0.145) or normoxia (FiO2: 0.209). Arterial oxygen saturation was assessed before the first Wingate effort, while blood lactate concentration and ratings of perceived exertion were measured after each bout. Results: Mean (P = .92) and peak (P = .63) power outputs, total work (P = .98), and the percentage decrement score (P = .25) were similar between conditions. Arterial oxygen saturation was significantly lower in hypoxia versus normoxia (92.0% [2.8%] vs 98.1% [0.4%], P < .01), whereas blood lactate concentration (P = .78) and ratings of perceived exertion (P = .51) did not differ between conditions. Conclusion: In sprinters, acute exposure to moderate hypoxia had no detrimental effect on RW performance and associated metabolic and perceptual responses.


2020 ◽  
Vol 15 (5) ◽  
pp. 714-719
Author(s):  
Sarah J. Willis ◽  
Grégoire P. Millet ◽  
Fabio Borrani

Purpose: To assess tissue oxygenation, along with metabolic and physiological responses during blood flow restriction (BFR, bilateral vascular occlusion) and systemic hypoxia conditions during submaximal leg- versus arm-cycling exercise. Methods: In both legs and arms, 4 randomized sessions were performed (normoxia 400 m, fraction of inspired oxygen [FIO2] 20.9% and normobaric hypoxia 3800 m, FIO2 13.1% [0.1%]; combined with BFR at 0% and 45% of resting pulse elimination pressure). During each session, a single 6-minute steady-state submaximal exercise was performed to measure physiological changes and oxygenation (near-infrared spectroscopy) of the muscle tissue in both the vastus lateralis (legs) and biceps brachii (arms). Results: Total hemoglobin concentration ([tHb]) was 65% higher (P < .001) in arms versus legs, suggesting that arms had a greater blood perfusion capacity than legs. Furthermore, there were greater changes in tissue blood volume [tHb] during BFR compared with control conditions (P = .017, F = 5.45). The arms elicited 7% lower tissue saturation (P < .001) and were thus more sensitive to the hypoxia-induced reduction in oxygen supply than legs, no matter the condition. This indicates that legs and arms may elicit different regulatory hemodynamic mechanisms (ie, greater blood flow in arms) for limiting the decreased oxygen delivery during exercise with altered arterial oxygen content. Conclusions: The combination of BFR and/or hypoxia led to increased [tHb] in both limbs likely due to greater vascular resistance; further, arms were more responsive than legs. This possibly influences the maintenance of oxygen delivery and enhances perfusion pressure, suggesting greater vascular reactivity in arms than in legs.


2019 ◽  
Vol 44 (6) ◽  
pp. 637-644
Author(s):  
Toshiharu Natsume ◽  
Toshinori Yoshihara ◽  
Hisashi Naito

Neuromuscular electrical stimulation (NMES) combined with blood flow restriction (BFR) induces muscle hypertrophy. However, cellular mechanisms underlying the muscle hypertrophy induced by NMES combined with BFR remain unclear. We tested the hypothesis that NMES combined with BFR would enhance the mechanistic target of rapamycin (mTOR) and mitogen-activated protein kinase (MAPK) signaling pathways. Age-matched male Wistar rats (6 months old, n = 7 per group) were assigned randomly to control, BFR alone (BFR), NMES alone (NMES), and NMES combined with BFR (NMES/BFR) groups. NMES induced 25 isometric contractions lasting 8 s with 4-s resting periods between contractions in the gastrocnemius muscle. Four sets in total were performed, with 1-min intervals between sets. A latex cuff was placed on the proximal portion of the hind limb and BFR at 200 mm Hg was conducted in 4 sets (each set 5 min) with 1-min rest intervals between sets. Venous blood was collected from the lateral tail vein to determine pH, H+ concentration, and lactate concentration before and immediately after the treatments. Expression levels of proteins related to muscle hypertrophy were determined by Western blot analysis. The application of NMES/BFR promoted muscle fatigue more than NMES alone. NMES/BFR induced greater changes in accumulation of metabolites and increase in gastrocnemius muscle weight. The phosphorylation of mTOR and MAPK signaling-related proteins was also enhanced following NMES/BFR, compared with other conditions. Thus, NMES enhanced the activation of mTOR and MAPK signaling pathways when combined with BFR.


2019 ◽  
Vol 119 (8) ◽  
pp. 1819-1828 ◽  
Author(s):  
Sarah J. Willis ◽  
Fabio Borrani ◽  
Grégoire P. Millet

2019 ◽  
Vol 20 (13) ◽  
pp. 3249 ◽  
Author(s):  
Johanna Vogel ◽  
Daniel Niederer ◽  
Tobias Engeroff ◽  
Lutz Vogt ◽  
Christian Troidl ◽  
...  

Background: The effects of blood flow restriction (training) may serve as a model of peripheral artery disease. In both conditions, circulating micro RNAs (miRNAs) are suggested to play a crucial role during exercise-induced arteriogenesis. We aimed to determine whether the profile of circulating miRNAs is altered after acute resistance training during blood flow restriction (BFR) as compared with unrestricted low- and high-volume training, and we hypothesized that miRNA that are relevant for arteriogenesis are affected after resistance training. Methods: Eighteen healthy volunteers (aged 25 ± 2 years) were enrolled in this three-arm, randomized-balanced crossover study. The arms were single bouts of leg flexion/extension resistance training at (1) 70% of the individual single-repetition maximum (1RM), (2) at 30% of the 1RM, and (3) at 30% of the 1RM with BFR (artificially applied by a cuff at 300 mm Hg). Before the first exercise intervention, the individual 1RM (N) and the blood flow velocity (m/s) used to validate the BFR application were determined. During each training intervention, load-associated outcomes (fatigue, heart rate, and exhaustion) were monitored. Acute effects (circulating miRNAs, lactate) were determined using pre-and post-intervention measurements. Results: All training interventions increased lactate concentration and heart rate (p < 0.001). The high-intensity intervention (HI) resulted in a higher lactate concentration than both lower-intensity training protocols with BFR (LI-BFR) and without (LI) (LI, p = 0.003; 30% LI-BFR, p = 0.008). The level of miR-143-3p was down-regulated by LI-BFR, and miR-139-5p, miR-143-3p, miR-195-5p, miR-197-3p, miR-30a-5p, and miR-10b-5p were up-regulated after HI. The lactate concentration and miR-143-3p expression showed a significant positive linear correlation (p = 0.009, r = 0.52). A partial correlation (intervention partialized) showed a systematic impact of the type of training (LI-BFR vs. HI) on the association (r = 0.35 remaining after partialization of training type). Conclusions: The strong effects of LI-BFR and HI on lactate- and arteriogenesis-associated miRNA-143-3p in young and healthy athletes are consistent with an important role of this particular miRNA in metabolic processes during (here) artificial blood flow restriction. BFR may be able to mimic the occlusion of a larger artery which leads to increased collateral flow, and it may therefore serve as an external stimulus of arteriogenesis.


Author(s):  
Naoya Takei ◽  
Jacky Soo ◽  
Hideo Hatta ◽  
Olivier Girard

Background: Compared with normoxia, repeated short (5–10 s) sprints (>10 efforts) with incomplete recovery (≤30 s) in hypoxia likely cause substantial performance reduction accompanied by larger metabolic disturbances and magnitude of neuromuscular fatigue. However, the effects of hypoxia on performance of repeated long (30 s) “all-out” efforts with near complete recovery (4.5 min) and resulting metabolic and neuromuscular adjustments remain unclear. Purpose: The intention was to compare acute performance, metabolic, and neuromuscular responses across repeated Wingates between hypoxia and normoxia. Methods: On separate visits, 6 male participants performed 4 × 30-second Wingate efforts with 4.5-minute recovery in either hypoxia (fraction of inspired oxygen: 0.145) or normoxia. Responses to exercise (muscle and arterial oxygenation trends, heart rate, and blood lactate concentration) and the integrity of neuromuscular function in the knee extensors were assessed for each exercise bout. Results: Mean (P = .80) and peak (P = .92) power outputs, muscle oxygenation (P = .88), blood lactate concentration (P = .72), and perceptual responses (all Ps > .05) were not different between conditions. Arterial oxygen saturation was significantly lower, and heart rate higher, in hypoxia versus normoxia (P < .001). Maximal voluntary contraction force and peripheral fatigue indices (peak twitch force and doublets at low and high frequencies) decreased across efforts (all Ps < .001) irrespective of conditions (all Ps > .05). Conclusion: Despite heightened arterial hypoxemia and cardiovascular solicitation, hypoxic exposure during 4 repeated 30-second Wingate efforts had no effect on performance and accompanying metabolic and neuromuscular adjustments.


2017 ◽  
Vol 12 (2) ◽  
pp. 152-160 ◽  
Author(s):  
Rachel Borne ◽  
Christophe Hausswirth ◽  
François Bieuzen

Purpose:To investigate the effect of different limb blood-flow levels on cycling-performance recovery, blood lactate concentration, and heart rate.Methods:Thirty-three high-intensity intermittent-trained athletes completed two 30-s Wingate anaerobic test sessions, 3 × 30-s (WAnT 1–3) and 1 × 30-s (WAnT 4), on a cycling ergometer. WAnT 1–3 and WAnT 4 were separated by a randomly assigned 24-min recovery intervention selected from among blood-flow restriction, passive rest, placebo stimulation, or neuromuscular electrical-stimulation-induced blood flow. Calf arterial inflow was measured by venous occlusion plethysmography at regular intervals throughout the recovery period. Performance was measured in terms of peak and mean power output during WAnT 1 and WAnT 4.Results:After the recovery interventions, a large (r = .68 [90% CL .42; .83]) and very large (r = .72 (90% CL .49; .86]) positive correlation were observed between the change in calf arterial inflow and the change in mean and peak power output, respectively. Calf arterial inflow was significantly higher during the neuromuscular-electrical-stimulation recovery intervention than with the blood-flow-restriction, passive-rest, and placebo-stimulation interventions (P < .001). This corresponds to the only intervention that allowed performance recovery (P > .05). No recovery effect was linked to heart rate or blood lactate concentration levels.Conclusions:For the first time, these data support the existence of a positive correlation between an increase in blood flow and performance recovery between bouts of high-intensity exercise. As a practical consideration, this effect can be obtained by using neuromuscular electrical stimulation-induced blood flow since this passive, simple strategy could be easily applied during short-term recovery.


Author(s):  
Johanna Sieland ◽  
Daniel Niederer ◽  
Tobias Engeroff ◽  
Lutz Vogt ◽  
Christian Troidl ◽  
...  

Abstract Purpose Physical activity is associated with altered levels of circulating microRNAs (ci-miRNAs). Changes in miRNA expression have great potential to modulate biological pathways of skeletal muscle hypertrophy and metabolism. This study was designed to determine whether the profile of ci-miRNAs is altered after different approaches of endurance exercise. Methods Eighteen healthy volunteers (aged 24 ± 3 years) participated this three-arm, randomized-balanced crossover study. Each arm was a single bout of treadmill-based acute endurance exercise at (1) 100% of the individual anaerobic threshold (IANS), (2) at 80% of the IANS and (3) at 80% of the IANS with blood flow restriction (BFR). Load-associated outcomes (fatigue, feeling, heart rate, and exhaustion) as well as acute effects (circulating miRNA patterns and lactate) were determined. Results All training interventions increased the lactate concentration (LC) and heart rate (HR) (p < 0.001). The high-intensity intervention (HI) resulted in a higher LC than both lower intensity protocols (p < 0.001). The low-intensity blood flow restriction (LI-BFR) protocol led to a higher HR and higher LC than the low-intensity (LI) protocol without BFR (p = 0.037 and p = 0.003). The level of miR-142-5p and miR-197-3p were up-regulated in both interventions without BFR (p < 0.05). After LI exercise, the expression of miR-342-3p was up-regulated (p = 0.038). In LI-BFR, the level of miR-342-3p and miR-424-5p was confirmed to be up-regulated (p < 0.05). Three miRNAs and LC show a significant negative correlation (miR-99a-5p, p = 0.011, r = − 0.343/miR-199a-3p, p = 0.045, r = − 0.274/miR-125b-5p, p = 0.026, r = − 0.302). Two partial correlations (intervention partialized) showed a systematic impact of the type of exercise (LI-BFR vs. HI) (miR-99a-59: r = − 0.280/miR-199a-3p: r = − 0.293). Conclusion MiRNA expression patterns differ according to type of activity. We concluded that not only the intensity of the exercise (LC) is decisive for the release of circulating miRNAs—as essential is the type of training and the oxygen supply.


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