The Acute Resting Metabolic Response to Energy Deficit caused by Increased Expenditure vs. Caloric Restriction.

According to the developmental origins of health and disease (DOHaD) hypothesis, changes in the maternal environment are known to reprogram the metabolic response of offspring. Known for its redox modulation, caloric restriction extends the lifespan of some species, which contributes to diminished cellular damage. Little is known about the effects of gestational caloric restriction, in terms of antioxidant parameters and molecular mechanisms of action, on the reproductive organs of offspring. This study assessed the effects of moderate (20%) caloric restriction on redox status parameters, molecular expression of sirtuin (SIRT) 1 and SIRT3 and histopathological markers in the ovaries and testes of adult rats that were subjected to gestational caloric restriction. Although enzyme activity was increased, ovaries from female pups contained high levels of oxidants, whereas testes from male pups had decreased antioxidant enzyme defences, as evidenced by diminished glyoxalase I activity and reduced glutathione content. Expression of SIRT3, a deacetylase enzyme related to cellular bioenergetics, was increased in both ovaries and testes. Previous studies have suggested that, in ovaries, diminished antioxidant metabolism can lead to premature ovarian failure. Unfortunately, there is little information regarding the redox profile in the testis. This study is the first to assess the redox network in both ovaries and testes, suggesting that, although intrauterine caloric restriction improves molecular mechanisms, it has a negative effect on the antioxidant network and redox status of reproductive organs of young adult rats.

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The Impact of Prescribed Exercise and Short-Term Caloric Restriction on Moderate-to-Vigorous Physical Activity (P08-011-19)

Current Developments in Nutrition ◽

10.1093/cdn/nzz044.p08-011-19 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

Author(s):

Alexandra Martin ◽

Birgit Wallmann-Sperlich ◽

Billy Sperlich ◽

Karsten Koehler

Keyword(s):

Physical Activity ◽

Weight Loss ◽

Energy Balance ◽

Caloric Restriction ◽

Repeated Measures ◽

Vigorous Physical Activity ◽

Energy Deficit ◽

Short Term ◽

Food And Agriculture ◽

The Impact

Abstract Objectives Weight loss, especially when achieved by caloric restriction (CR), reduces total daily energy expenditure (EE), which can attenuate further weight loss. Although exercise is a common countermeasure to the decline in EE, it is unknown whether prescribed exercise leads to compensatory changes in moderate-to-vigorous physical activities (MVPA) during non-exercise periods in the context of CR. The present study sought to quantify changes in MVPA in response to an energetically-matched energy deficit induced by CR alone or combined with exercise. We hypothesized that MVPA outside of prescribed exercise would be greater during non-exercise conditions, regardless of energy balance. Methods In a repeated-measures crossover design, active men (n = 6, 25 ± 1.0 y) underwent four 4-day conditions: CR with exercise (CR + X), CR without exercise (CR–X), energy-balanced control (CON) with exercise (CON + X) and without exercise (CON–X). Dietary intake was manipulated such that energy availability (EA) was 15 kcal·kg FFM−1·day−1 (CR) or 40 kcal·kg FFM−1·day−1 (CON). Prescribed exercise EE was 15 kcal·kg FFM−1·day−1. Physical activity was assessed using the SenseWear Pro3 armband (Bodymedia, Pittsburgh, USA) to quantify time spent in MVPA and light activities (sleep, lying down without sleep, and non-lying light activities) as % of total wear time. Results EA did not differ between CR (P = 0.87) nor CON (P = 0.42). As expected, weight loss was significant (P < 0.001) in CR + EX (–1.8 ± 0.4 kg) and CR-EX (–2.4 ± 0.3 kg). After deducting prescribed exercise, there was a significant effect of exercise on time spent in MVPA (P = 0.02), in that MVPA was lower during CON-EX vs. CON + EX (11.4 ± 2.0% vs. 17.9 ± 2.1%, P = 0.03) and trended lower during CR-EX vs. CR + EX (13.6 ± 1.5% vs. 15.5 ± 1.6%, P = 0.08). In exercise conditions, MVPA was lower during CR + EX when compared to CON + EX (P = 0.03). Conclusions Independent of energy balance, engaging in short-term exercise led to more, not less, time spent in non-exercise MVPA. These findings indicate the prevention of reductions in non-exercise activity as an additional benefit of incorporating exercise into weight loss interventions. Funding Sources The study was supported in part by the USDA National Institute of Food and Agriculture and institutional funding from the University of Nebraska-Lincoln.

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