A randomized controlled trial to isolate the effects of fasting and energy restriction on weight loss and metabolic health in lean adults

Intermittent fasting may impart metabolic benefits independent of energy balance by initiating fasting-mediated mechanisms. This randomized controlled trial examined 24-hour fasting with 150% energy intake on alternate days for 3 weeks in lean, healthy individuals (0:150; n = 12). Control groups involved a matched degree of energy restriction applied continuously without fasting (75% energy intake daily; 75:75; n = 12) or a matched pattern of fasting without net energy restriction (200% energy intake on alternate days; 0:200; n = 12). Primary outcomes were body composition, components of energy balance, and postprandial metabolism. Daily energy restriction (75:75) reduced body mass (−1.91 ± 0.99 kilograms) almost entirely due to fat loss (−1.75 ± 0.79 kilograms). Restricting energy intake via fasting (0:150) also decreased body mass (−1.60 ± 1.06 kilograms; P = 0.46 versus 75:75) but with attenuated reductions in body fat (−0.74 ± 1.32 kilograms; P = 0.01 versus 75:75), whereas fasting without energy restriction (0:200) did not significantly reduce either body mass (−0.52 ± 1.09 kilograms; P ≤ 0.04 versus 75:75 and 0:150) or fat mass (−0.12 ± 0.68 kilograms; P ≤ 0.05 versus 75:75 and 0:150). Postprandial indices of cardiometabolic health and gut hormones, along with the expression of key genes in subcutaneous adipose tissue, were not statistically different between groups (P > 0.05). Alternate-day fasting less effectively reduces body fat mass than a matched degree of daily energy restriction and without evidence of fasting-specific effects on metabolic regulation or cardiovascular health.

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OR31-07 Increased Caloric Intake Improves Regularity of Menses and Is Associated with Increased TT3 and Leptin in Exercising Women with Oligo/amenorrhea: The “REFUEL” Randomized Controlled Trial

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa046.1946 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

Author(s):

Mary Jane De Souza ◽

Rebecca J Mallinson ◽

Emily A Southmayd ◽

Nicole C A Strock ◽

Kristen J Koltun ◽

...

Keyword(s):

Randomized Controlled Trial ◽

Energy Intake ◽

Body Mass ◽

Fat Mass ◽

Eating Habits ◽

Controlled Trial ◽

Randomized Controlled ◽

Exercising Women ◽

Increase Energy Intake ◽

Treatment Plans

Abstract Exercising women often fail to consume adequate energy intake relative to energy expenditure and are thus susceptible to menstrual disturbances and poor bone health secondary to energy deficiency. Ideal treatment plans are to increase energy intake to reverse energetic suppression. The purpose of this study was to determine if REFUEL, a 12-month randomized controlled trial (RCT) of increased energy intake, improves menstrual frequency and markers of energetic status in exercising women with oligo/amenorrhea. Young, exercising women with oligo/amenorrhea were randomized into two groups. The treatment group (Oligo/Amen+Cal, n=32) increased energy intake 20-40% above baseline energy needs and the Oligo/Amen Control group (n=30) maintained exercise and eating habits for the 12-month intervention. Menses was tracked throughout the intervention by menstrual calendars and daily urine samples, energetic status was assessed by body composition and total triiodothyronine (TT3) and leptin concentrations. Conditional recurrent events Cox Proportional Hazards model tested the effects of the intervention and multi-level modelling assessed relationships among variables. There was a significant group*time interaction for body mass, percent body fat, fat mass, and TT3 concentrations (p<0.03), such that Oligo/Amen+Cal women gained more body and fat mass and had a greater increase in TT3 during the study compared to Oligo/Amen Controls. Specifically, Oligo/Amen+Cal women (21.6 yrs, BMI: 20.2 kg/m2) increased energy intake by 353 kcal/d and gained 1.9 kg of body mass, corresponding to increased fat mass (1.2 kg) and leptin (64%). Oligo/Amen Controls (20.9 yrs, BMI: 21.3 kg/m2) had no change (-32 kcal/d) in energy intake (p<0.001 vs. Oligo/Amen+Cal) and minimal change in body mass (0.8 kg; p=0.04 vs. Oligo/Amen+Cal), fat mass (0.4 kg; p=0.08 vs. Oligo/Amen+Cal), and leptin (21% increase, p=0.07 vs. Oligo/Amen+Cal). Controlling for baseline BMI and menstrual status, the intervention increased the likelihood of experiencing menses (p<0.001) such that Oligo/Amen+Cal women were twice as likely (104% increase) to experience menses during the intervention compared to Oligo/Amen Controls. Further, the higher the BMI at baseline, the greater the likelihood of experiencing a menses such that for every kg/m2 increase in BMI the likelihood of menses increased by 10%. Overall, a nutritional intervention designed to increase energy intake by a moderate amount in exercising women with oligo/amenorrhea successfully improved body mass and fat mass, concentrations of metabolic hormones, and the likelihood of experiencing menses compared to oligo/amenorrheic women who maintained exercise and eating habits. As such, treatment plans designed to increase energy intake can be successful in reversing energetic suppression and recovering menses.

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Correction: High intensity, circuit-type integrated neuromuscular training alters energy balance and reduces body mass and fat in obese women: A 10-month training-detraining randomized controlled trial

PLoS ONE ◽

10.1371/journal.pone.0240945 ◽

2020 ◽

Vol 15 (10) ◽

pp. e0240945

Author(s):

Alexios Batrakoulis ◽

Athanasios Z. Jamurtas ◽

Kalliopi Georgakouli ◽

Dimitrios Draganidis ◽

Chariklia K. Deli ◽

...

Keyword(s):

Randomized Controlled Trial ◽

Energy Balance ◽

Body Mass ◽

High Intensity ◽

Controlled Trial ◽

Neuromuscular Training ◽

Obese Women ◽

Randomized Controlled

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Body fat loss and compensatory mechanisms in response to different doses of aerobic exercise—a randomized controlled trial in overweight sedentary males

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00141.2012 ◽

2012 ◽

Vol 303 (6) ◽

pp. R571-R579 ◽

Cited By ~ 79

Author(s):

Mads Rosenkilde ◽

Pernille Auerbach ◽

Michala Holm Reichkendler ◽

Thorkil Ploug ◽

Bente Merete Stallknecht ◽

...

Keyword(s):

Randomized Controlled Trial ◽

Body Composition ◽

Energy Balance ◽

Aerobic Exercise ◽

Body Fat ◽

Controlled Trial ◽

Negative Energy ◽

Compensatory Mechanisms ◽

Randomized Controlled ◽

Exercise Induced

The amount of weight loss induced by exercise is often disappointing. A diet-induced negative energy balance triggers compensatory mechanisms, e.g., lower metabolic rate and increased appetite. However, knowledge about potential compensatory mechanisms triggered by increased aerobic exercise is limited. A randomized controlled trial was performed in healthy, sedentary, moderately overweight young men to examine the effects of increasing doses of aerobic exercise on body composition, accumulated energy balance, and the degree of compensation. Eighteen participants were randomized to a continuous sedentary control group, 21 to a moderate-exercise (MOD; 300 kcal/day), and 22 to a high-exercise (HIGH; 600 kcal/day) group for 13 wk, corresponding to ∼30 and 60 min of daily aerobic exercise, respectively. Body weight (MOD: −3.6 kg, P < 0.001; HIGH: −2.7 kg, P = 0.01) and fat mass (MOD: −4.0 kg, P < 0.001 and HIGH: −3.8 kg, P < 0.001) decreased similarly in both exercise groups. Although the exercise-induced energy expenditure in HIGH was twice that of MOD, the resulting accumulated energy balance, calculated from changes in body composition, was not different (MOD: −39.6 Mcal, HIGH: −34.3 Mcal, not significant). Energy balance was 83% more negative than expected in MOD, while it was 20% less negative than expected in HIGH. No statistically significant changes were found in energy intake or nonexercise physical activity that could explain the different compensatory responses associated with 30 vs. 60 min of daily aerobic exercise. In conclusion, a similar body fat loss was obtained regardless of exercise dose. A moderate dose of exercise induced a markedly greater than expected negative energy balance, while a higher dose induced a small but quantifiable degree of compensation.

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