Six weeks of static apnea training does not affect Hbmass and exercise performance

Abstract

Purpose: Acute apnea is known to induce decreases in oxyhemoglobin desaturation (SpO2) and increases in erythropoietin concentration ([EPO]). This study examined the potential of an apnea training program to induce erythropoiesis and increase hematological parameters and exercise performance. Methods: Twenty-two male subjects were randomly divided into an apnea and control group. The apnea group performed a 6-week apnea training program consisting of a daily series of 5 maximal static apneas. Before and after training, subjects visited the lab on three test days to perform 1) a ramp incremental test measuring V̇O2peak, 2) CO-rebreathing for Hb mass determination and a 3-km time trial and 3) an apnea test protocol with continuous finger SpO2 registration. Venous blood samples were drawn before and 180 minutes after the apnea test for analysis of [EPO]. Results: Minimal SpO2 reached during the apnea test protocol was 91 ±7% pre and 82 ±7% post apnea training. The apnea test protocol did not elicit an acute increase in [EPO] (p=0.685) before nor after the training program. Consequently, resting [EPO] (p=0.170), Hbmass (p=0.134), V̇O2peak (p=0.796) and 3-km cycling time trial performance (p=0.509) were not affected either. Conclusion: The apnea test and training protocol, consisting of 5 maximal static apneas, did not induce a sufficiently strong hypoxic stimulus to cause erythropoiesis and therefore did not result in an increase in resting [EPO], Hbmass, V̇O2peak or time trial performance. Longer and/or more intense training sessions inducing a stronger hypoxic stimulus are probably needed to obtain changes in hematological and exercise parameters.

Effects of apnoea training on aerobic and anaerobic performance: A systematic review and meta-analysis

“…Previous reviews consulted (Lemaitre, 2009;Schagatay, 2010;Elia et al, 2021) all agree that ApT might be an effective alternative to increase hematocrit, EPO, Hb and lung volume; all of them predictors of aerobic fitness. However, in stark contrast, the randomised control trials included in this review (Woorons, 2008;Woorons et al, 2016;Fernandez et al, 2018;Bouten et al, 2022) suggest no effects of ApT on aerobic performance measured by VO 2max . It is of course acknowledged that there are many other parameters of endurance performance, beyond VO 2max , that are arguably more ecologically valid and these were not assessed in the reported studies.…”

“…Table 2 shows the participant characteristics of the seven studies included in this meta-analysis (total sample size of 127 participants, age 27 ± 9 years old) ( Woorons, 2008 ; Woorons et al, 2019 , 2016 ; Trincat et al, 2017 ; Fernandez et al, 2018 ; Fornasier-Santos et al, 2018 ; Bouten et al, 2022 ). The total pool of participants was allocated to either ApT ( n = 64) or NB ( n = 63).…”

“…A total of four studies analyzed the effects of ApT on aerobic exercise performance ( Woorons, 2008 ; Woorons et al, 2016 ; Fernandez et al, 2018 ; Bouten et al, 2022 ), with VO 2max the only variable reported. The overall quality of evidence was judged to be moderate evidence on VO 2max ( Table 1 ).…”

“…In the studies included in this review ( Woorons, 2008 ; Woorons et al, 2019 , 2016 ; Trincat et al, 2017 ; Fernandez et al, 2018 ; Fornasier-Santos et al, 2018 ; Bouten et al, 2022 ), it was reported that athletes could train under hypoxic conditions at sea level through apnoea training at low lung volumes (LLV, i.e., “end-expiratory” breath-hold). During such exercise with ApT at LLV, arterial oxygen saturation dropped to severe hypoxaemia.…”

“…Previous reviews suggested that breath-hold divers display beneficial adaptations primarily as a consequence of exposure to training-induced stimuli ( Elia et al, 2021 ), that might contribute to improved sports performance ( Lemaître et al, 2010 ). These adaptations have led researchers to explore the possible use of apnoea training beyond freediving as a means of enhancing performance markers such as: 100, 200 and 400 m swimming time trial ( Stavrou et al, 2015 ; Woorons et al, 2016 ); 3 km cycling time trial ( Bouten et al, 2022 ); or repeated sprint ability (RSA) ( Trincat et al, 2017 ; Fornasier-Santos et al, 2018 ; Woorons et al, 2019 ), defined as an important attribute for athletes competing in high-intensity intermittent sports, such as soccer, basketball, handball, tennis, etc ( Bishop and Spencer, 2004 ).…”