Effects of a blood flow restriction exercise under different pressures on testosterone, growth hormone, and insulin-like growth factor levels

Abstract

Objective To investigate the changes in serum growth hormone (GH), testosterone, and insulin-like growth factor 1 (IGF-1) during low-intensity resistance exercise under different cuff pressures. Methods We performed a single-blind, cross-over design study. Twenty-five healthy young men performed three exercise protocols as follows: 1) no blood flow restriction exercise (control group), 2) resistance exercise at 40% of arterial occlusion pressure (AOP) (low group), and 3) resistance exercise at 70% of AOP (high group). Blood lactate, GH, testosterone, and IGF-1 levels were measured at four time points. Results There were no differences in the indices before exercise. The blood flow restriction exercise under different pressures had different effects on each index and there was an interactive effect. GH levels were significantly higher in the high group than in the other groups after exercise. Immediately after exercise, IGF-1 and testosterone levels were significantly higher in the high group than in the other groups. At 15 minutes after exercise, testosterone levels were significantly higher in the high group than in the other groups. Conclusions Low-intensity resistance exercise combined with blood flow restriction effectively increases GH, IGF-1, and testosterone levels in young men. Increasing the cuff pressure results in greater levels of hormone secretion.

Acute and Chronic Bone Marker and Endocrine Responses to Resistance Exercise With and Without Blood Flow Restriction in Young Men

“…Cortisol decreased from week 1 to week 6 in all groups, which also was not explained by plasma volume changes. Our findings agree with previous studies documenting increases in testosterone ( Madarame et al, 2010 ; Yinghao et al, 2021 ) and IGF-1 ( Takano et al, 2005 ; Madarame et al, 2010 ; Yinghao et al, 2021 ) and no change in cortisol ( Patterson et al, 2013 ) in response to a single bout of BFR resistance exercise. Few studies have examined the endocrine adaptations to BFR resistance training programs.…”

“…Possible mechanisms for the adaptations that occur with BFR exercise include enhanced metabolic stress resulting from the accumulation of metabolic by-products in the occluded limbs affecting fast-twitch motor unit recruitment and the secretion of hormones and factors that promote protein synthesis and angiogenesis ( Takarada et al, 2000 ; Suga et al, 2012 ; Karabulut et al, 2014 ). Acute bouts of BFR resistance exercise stimulate increases in blood lactate and anabolic hormones (e.g., growth hormone, testosterone, insulin-like growth factor-1, IGF-1) with minimal changes in muscle damage markers ( Takarada et al, 2000 ; Abe et al, 2005 ; Takano et al, 2005 ; Madarame et al, 2010 ; Manini et al, 2012 ; Yinghao et al, 2021 ). Another mechanism is the activation of localized chemoreceptors and exercise-induced muscle swelling, often observed following BFR exercise, that may play a role in shifting the protein balance toward anabolism.…”

“…Chronically elevated cortisol is associated with bone loss and increased bone fragility ( Hamdy and Appelman-Dijkstra, 2019 ). Acute bouts of BFR resistance exercise have been shown to stimulate significant increases in testosterone ( Madarame et al, 2010 ; Yinghao et al, 2021 ) and IGF-1 ( Takano et al, 2005 ; Madarame et al, 2010 ; Yinghao et al, 2021 ) serum concentrations; however, the hormone adaptations to chronic BFR resistance training are not clear. Abe et al (2005) reported a significant increase in resting serum IGF-1 concentrations after 2 weeks of BFR resistance training in young men, whereas Karabulut et al (2013) found no significant changes in resting IGF-1, testosterone, or insulin-like growth factor binding protein-3 (IGFBP-3) serum concentrations in response to 6 weeks of either low intensity BFR or high intensity resistance training in older men.…”

Blood-Flow-Restriction-Training-Induced Hormonal Response is not Associated with Gains in Muscle Size and Strength

“…In the present study, there was an increase in lactate concentration in all groups and an increase in GH concentration 15 min after exercise in the LL-BFR and HL groups. In fact, these findings corroborate some other studies (Kim et al, 2014;Ozaki et al, 2017;Yinghao et al, 2021), however, no association was found between the acute changes in lactate concentrations or GH and training-induced gains in muscle size and strength. Only a significant relationship was observed between changes in lactate concentrations and 1RM or the CSA in the LL group (Table 1).…”

Effects of functional training with blood occlusion on the irisin, follistatin, and myostatin myokines in elderly men

“…The primary physiological mechanism of BFR is tissue ischemia, which results in the accumulation of byproducts and cellular swelling, leading to the release of growth factors [ 27 ]. It was shown that training with BFR substantially increases blood lactate, growth hormone, and insulin-like growth factor-1 concentrations [ 28 , 29 ], which ultimately up-regulate protein synthesis, leading to maintaining or improving muscle mass. Hence, we assumed that using BFR during FT generates further physiological adaptations in the older adult population.…”