Effects of exercise training at lactate threshold and detraining for 12 weeks on body composition, aerobic performance, and stress related variables in obese women

Kim

et al. 2020

JOMES

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Background:The present study examined the effects of a prolonged exercise intervention at the lactate threshold (LT) on body composition, aerobic performance, and the autonomic nervous system (ANS) in women with obesity. Methods: A total of 36 obese Korean women aged 36 to 55 years (mean±standard deviation, 44.8±5.2 years) were randomly assigned to a control group (CON, n=18) or an experimental group (EXP, n=18); and EXP underwent aerobic exercise training three times a week at a heart rate corresponding to the LT (HR_LT) for 12 weeks. All dependent variables (body composition, aerobic performance, and ANS function parameters) were evaluated before and after training. Results: Compared with the CON group, the EXP group showed significant improvement in body composition (body weight, −4.57 vs. −2.40 kg; body mass index, −1.79 vs. −0.96 kg/m 2 ; %body fat, −4.63 vs. −1.41; fat-free mass, 3.24 vs. -0.08 kg), aerobic performance (oxygen consumption at LT, 5.74 vs. 0.12 mL/kg/min; maximal oxygen consumption, 5.41 vs. 2.14 mL/kg/min; treadmill speed at HR_LT, 1.40 vs. 0.29 km/hr; bicycle load at HR_LT, 18.62 vs. 4.52 w; and ANS function (mean RR, 50.83 vs. −15.04 ms; standard deviation of NN intervals, 5.08 vs. −0.55 ms; root mean square of successive differences, 6.42 vs. 1.87 ms; total power, 0.34 vs. 0.10 ms 2 ; high frequency, 0.32 vs. −0.04 ms 2 ; low frequency/high frequency, −0.09 vs. 0.01). Conclusion: Aerobic exercise at the LT for 12 weeks is a practical method of improving body composition, aerobic performance, and ANS function for women with obesity.Obesity is an accumulation of excess fat, caused by energy imbalance between excess food intake and the calories consumed. 1 According to a report by the World Health Organization in 2014, more than 1.9 billion people, or 39% of the world's adult population, are overweight and 13%, or 6 million people, are obese. 2 As for the prevalence of obesity in Korea, the male obesity rate decreases with age (32% in 20s, 43.9% in 30s, 39.6% in 40s, 41.5% in 50s, 36.9% in 60s, and 24.0% in more than 70s). On the other hand, women's obesity rate increases rapidly with age (15.0% in 20s, 18.6% in 30s, 22.3% in 40s, 29.3% in 50s, 36.6% in 60s, and 37.3% in more than 70s). 3 This suggests that the obesity rate increases by age in women and 20 to 40 years old women who have a relatively low prevalence of obesity need long-term and continuous treatment for obesity.

Section: Discussionmentioning

confidence: 97%

“…Park et al 23 verified that a dietary intervention of 70% of recommended dietary allowance and exercise training corresponding to the heart rate at the LT for 12 weeks effectively improved body composition, aerobic performance, and stress. These findings show that moderate aerobic exercise can improve ANS function and prevent and treat obesity.…”

mentioning

confidence: 99%

Twelve Weeks of Aerobic Exercise at the Lactate Threshold Improves Autonomic Nervous System Function, Body Composition, and Aerobic Performance in Women with Obesity

Kim

et al. 2020

JOMES

Self Cite

“…Data from the remaining four subjects were discarded due to withdrawal ( n = 4). The required sample size was estimated using an effect size (ES = 0.49) reported in the effect of exercise on cardiopulmonary fitness [ 22 ]. With an alpha of 0.05 and the desired power of 0.80, the total sample size necessary to achieve statistical significance was estimated to be 12 participants.…”

Section: Methodsmentioning

confidence: 99%

Effects of Moderate Combined Resistance- and Aerobic-Exercise for 12 Weeks on Body Composition, Cardiometabolic Risk Factors, Blood Pressure, Arterial Stiffness, and Physical Functions, among Obese Older Men: A Pilot Study

Hong

et al. 2020

IJERPH

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We demonstrated the hypothesis that combined exercise improves body composition, cardiometabolic risk factors, blood pressure (BP), arterial stiffness, and physical functions, in obese older men. Older men (n = 20) were randomly assigned to combined exercise training (EXP; n = 10) or control groups (CON; n = 10). The combined exercise was comprised of elastic-band resistance training and walking/running on a treadmill and bicycle at 60–70% of maximal heart rate for 3 days/weeks. EXP showed significant decreases in body weight, body mass index, and %body fat (p < 0.05). The exercise program significantly reduced BP, mean arterial pressure, pulse pressure, and brachial-ankle pulse wave velocity. Furthermore, while the plasma levels of low-density lipoprotein cholesterol and epinephrine were significantly reduced in EXP, VO2 peak and grip strength were significantly enhanced (p < 0.05). In conclusion, it is indicated that 12-week regular combined exercise improves body composition, cardiometabolic risk factors, hemodynamics, and physical performance in obese older men.

“…After approximately 10 min of rest, four pads were placed on the wrists and ankles using an HRV meter (LAXTHA; CANS-3000, Daejeon, Republic of Korea), and participants' HRV was measured in the resting condition. The following parameters were evaluated: standard deviation (SD) of successive differences (SDNN) and root mean square of successive differences (RMSSD) for the time domain methods and low frequency (LF) band, high frequency (HF) band, and LH/HF band ratio for the frequency domain methods [33]. All athletes performed the following in 90-min sessions: Warm-up, interval training, and cool-down.…”

Section: Ans Functionmentioning

confidence: 99%

Interval Hypoxic Training Enhances Athletic Performance and Does Not Adversely Affect Immune Function in Middle- and Long-Distance Runners

Kim

2020

IJERPH

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This study evaluated the effects of intermittent interval training in hypoxic conditions for six weeks compared with normoxic conditions, on hemodynamic function, autonomic nervous system (ANS) function, immune function, and athletic performance in middle- and long-distance runners. Twenty athletes were divided into normoxic training (normoxic training group (NTG); n = 10; residing and training at sea level) and hypoxic training (hypoxic training group (HTG); n = 10; residing at sea level but training in 526-mmHg hypobaric hypoxia) groups. All dependent variables were measured before, and after, training. The training frequency was 90 min, 3 d per week for six weeks. Body composition showed no significant difference between the two groups. However, the HTG showed more significantly improved athletic performance (e.g., maximal oxygen uptake). The hemodynamic function (e.g., oxygen uptake, oxygen pulse, and cardiac output) during submaximal exercise and ANS function (e.g., standard deviation and root mean square of successive differences, high frequency, and low/high frequency) improved more in the HTG. Immune function parameters were stable within the normal range before and after training in both groups. Therefore, hypoxic training was more effective in enhancing athletic performance, and improving hemodynamic and ANS function; further, it did not adversely affect immune function in competitive runners.