Effects of Living High-Training Low and High on Body Composition and Metabolic Risk Markers in Overweight and Obese Females

Abstract

This study examined the effects of 4 weeks of living high-training low and high (LHTLH) under moderate hypoxia on body weight, body composition, and metabolic risk markers of overweight and obese females. Nineteen healthy overweight or obese females participated in this study. Participants were assigned to the normoxic training group (NG) or the LHTLH group (HG). The NG participants lived and trained at sea level. The HG participants stayed for approximately 10 hours in a simulated 2300 m normobaric state of hypoxia for six days a week and trained for 2 hours 3 times a week under the same simulated hypoxia. The interventions lasted for 4 weeks. All groups underwent dietary restriction based on resting metabolic rate. The heart rate of the participants was monitored every ten minutes during exercise to ensure that the intensity was in the aerobic range. Compared with the preintervention values, body weight decreased significantly in both the NG and the HG (−8.81 ± 2.09% and −9.09 ± 1.15%, respectively). The fat mass of the arm, leg, trunk, and whole body showed significant reductions in both the NG and the HG, but no significant interaction effect was observed. The percentage of lean soft tissue mass loss in the total body weight loss tended to be lower in the HG (27.61% versus 15.94%, P=0.085). Between the NG and the HG, significant interaction effects of serum total cholesterol (−12.66 ± 9.09% versus −0.05 ± 13.36%,) and apolipoprotein A1 (−13.66 ± 3.61% versus −5.32 ± 11.07%, P=0.042) were observed. A slight increase in serum high-density lipoprotein cholesterol (HDL-C) was observed in the HG (1.12 ± 12.34%) but a decrease was observed in the NG (−11.36 ± 18.91%). The interaction effect of HDL-C between NG and HG exhibited a significant trend (P=0.055). No added effects on serum triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C), or APO-B were observed after 4 weeks of LHTLH. In conclusion, 4 weeks of LHTLH combined with dietary restriction could effectively reduce the body weight and body fat mass of overweight and obese females. Compared with training and sleeping under normoxia, no additive benefit of LHTLH on the loss of body weight and body fat mass was exhibited. However, LHTLH may help to relieve the loss of lean soft tissue mass and serum HDL-C.

BAIBA Involves in Hypoxic Training Induced Browning of White Adipose Tissue in Obese Rats

“…Previous studies conducted by our group reported that Hypoxic Training is effective in regulating lipid metabolism in obese rats. The findings showed that the main mechanisms involve skeletal muscle fatty acid metabolism and liver lipid metabolism ( Lu et al, 2014 ; Lu et al, 2016 ; Gao et al, 2020 ). However, effect of Hypoxic exercise on BAIBA secretion in obese rats has not been fully elucidated.…”

Exposure to Normobaric Hypoxia Combined with a Mixed Diet Contributes to Improvement in Lipid Profile in Trained Cyclists

“…Similar changes were also reported after living at moderate altitudes (days-weeks), where a decrease in TC and LDL-C levels [59][60][61] and an increase in HDL-C levels [61] were observed. In a recent study by Gao et al [62], the authors did not find statistically significant changes in the lipid profile following a four-week LH-TL protocol at a simulated altitude of 2300 m. It should be noted that these studies were performed with nontrained individuals and those with obesity and metabolic syndrome. A study involving athletes was conducted by Pialoux et al [63].…”

“…The mechanisms associated with the improvement of HDL-C after LH-TL are also unclear. In a recent study, Gao et al [62] suggested that exposure to hypoxia may prevent the loss of HDL-C due to the increased expression of the lipoprotein lipase gene as a result of hypoxia-induced factor 1 (HIF1) upregulation. Furthermore, the activation of HIF1 may enhance HDL particle synthesis by stimulating the expression of ATP-binding cassette transporter ABCA1 [72,73].…”

The effects of six weeks of fasted aerobic exercise on body shape and blood biochemical index in overweight and obese young adult males

“…In formal exercise we used Polar meter to monitor heart rate, so as to control the intensity of exercise, target heart rate = resting heart rate + heart rate reserve × 20%–40% (heart rate reserve = maximum heart rate - resting heart rate). 20 Subjects in each group exercised five days a week, once a day, for 30 min each time, with 20 min of preparatory and finishing activities before and after exercise. 21 They did not carry out any form of exercise training except for the exercise required in the experiment.…”