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To date, no research has explored the effects of low energy availability on cognitive performance using dietary and exercise regimens relevant to athletes. Twenty female participants (10 eumenorrheic, 10 oral contraceptive [OC] users) completed three 3-day conditions: 1) controlled-balanced energy availability without exercise (BAL; 45 kcal·kg lean body mass [LBM] -1 ·day -1 ); 2) diet-induced low energy availability without exercise (DIET; 15 kcal·kg LBM -1 ·day -1 ); and 3) exercise-induced low energy availability (EX; 15 kcal·kg LBM -1 ·day -1 , including 30 kcal·kg LBM -1 ·day -1 treadmill running at 70% maximal oxygen uptake). A cognitive test battery was completed before and after each 3-day condition. Mental rotation test accuracy improved in the BAL condition, but there was a decline in accuracy in the EX condition (BAL, +2.5%; EX, -1.4%; P  = 0.042, d  = 0.85). DIET (+1.3%) was not different to BAL or EX ( P  > 0.05). All other measures of cognitive performance were not affected by condition ( P  > 0.05) and OC use did not affect cognitive responses ( P  > 0.05). Accuracy in the mental rotation test was impaired when low energy availability was induced through increased exercise energy expenditure. All other aspects of cognition were unaffected by 3 days of low energy availability through diet or exercise. OC use did not mediate the effect of low energy availability on cognition. Novelty: Cognitive function was not affected by 3 days of diet-induced low energy availability. Only spatial awareness was impaired during 3 days of exercise-induced low energy availability. Reproductive hormones affected spatial awareness independent of energy availability.

Background: To inform public health interventions, further investigation is needed to identify: (1) frequency/intensity of everyday physical activity (PA) needed to reduce dementia risk; (2) whether post-diagnosis reduction in PA is associated with cognitive outcomes in people with dementia., Methods: Data from 11,391 men and women (aged ≥50) were obtained from the English Longitudinal Study of Ageing cohort. Assessments were carried out at baseline (2002-2003) and at biannual follow-ups (2004-2013)., Results: Older adults who carried out moderate to vigorous activity at least once per week had a 34%-50% lower risk for cognitive decline and dementia over an 8-10 year follow-up period. From pre- to post-dementia diagnosis, those who decreased PA levels had a larger decrease in immediate recall scores, compared to those who maintained or increased PA levels (analyses were adjusted for changes in physical function)., Conclusion: PA was associated with cognitive outcomes in a dose-dependent manner. Reduction in PA after diagnosis was associated with accelerated cognitive decline and maintaining PA may reduce symptom progression in dementia.

Background: An acute bout of exercise elicits a beneficial effect on subsequent cognitive function in adolescents. The effect of games-based activity, an ecologically valid and attractive exercise model for young people, remains unknown; as does the moderating effect of fitness on the acute exercise-cognition relationship. Therefore, the aim of the present study was to examine the effect of games-based activity on subsequent cognition in adolescents, and the moderating effect of fitness on this relationship., Methods: Following ethical approval, 39 adolescents (12.3 ± 0.7 year) completed an exercise and resting trial in a counterbalanced, randomised crossover design. During familiarisation, participants completed a multi-stage fitness test to predict VO 2 peak. The exercise trial consisted of 60-min games-based activity (basketball), during which heart rate was 158 ± 11 beats∙min - 1 . A battery of cognitive function tests (Stroop test, Sternberg paradigm, trail making and d2 tests) were completed 30-min before, immediately following and 45-min following the basketball., Results: Response times on the complex level of the Stroop test were enhanced both immediately (p = 0.021) and 45-min (p = 0.035) post-exercise, and response times on the five item level of the Sternberg paradigm were enhanced immediately post-exercise (p = 0.023). There were no effects on the time taken to complete the trail making test or any outcome of the d2 test. In particular, response times were enhanced in the fitter adolescents 45-min post-exercise on both levels of the Stroop test (simple, p = 0.005; complex, p = 0.040) and on the three item level of the Sternberg paradigm immediately (p = 0.017) and 45-min (p = 0.008) post-exercise., Conclusions: Games-based activity enhanced executive function and working memory scanning speed in adolescents, an effect particularly evident in fitter adolescents, whilst the high intensity intermittent nature of games-based activity may be too demanding for less fit children.

The aim of this study was to assess the relations of daily moderate-to-vigorous physical activity (MVPA) to cognitive functions in 15-year-old adolescents from the Avon Longitudinal Study of Parents and Children while controlling for aerobic fitness. A sub-sample of 667 adolescents (M(age) = 15.4 ± 0.16 years; 55% females) who provided valid data on variables of interest, were used in the analyses. MVPA was objectively assessed using an Actigraph GT1M accelerometer and aerobic fitness was expressed as physical work capacity at the heart rate of 170 beats per minute from a cycle ergometer test. A computerized stop-signal task was used to measure mean reaction time (RT) and standard deviation of RT, as indicators of cognitive processing speed and variability during an attention and inhibitory control task. MVPA was not significantly related to cognitive processing speed or variability of cognitive performance in hierarchical linear regression models. In simple regression models, aerobic fitness was negatively related to mean RT on the simple go condition. Our results suggest that aerobic fitness, but not MVPA, was associated with cognitive processing speed under less cognitively demanding task conditions. The results thus indicate a potential global effect of aerobic fitness on cognitive functions in adolescents but this may differ depending on the specific task characteristics.

The aim of the present study was to examine the combined effects of breakfast glycaemic index (GI) and a mid-morning bout of exercise on adolescents' cognitive function. Participants were randomly allocated to a high or low GI breakfast group in a mixed research design, where each participant completed two experimental trials (exercise and resting). Forty-two adolescents (12.4±0.5 years old), undertook a bout of exercise (ten repeats of level one of the multi-stage fitness test; exercise trial) or continued to rest (resting trial) following consumption of either a high or low GI breakfast. A battery of cognitive function tests (visual search test, Stroop test and Sternberg paradigm) was completed 30 min before and 45 min following the exercise. Average heart rate during exercise was 170±15 beats·min(-1). On the complex level of the Stroop test, response times improved across the morning following the low GI breakfast on both the exercise and resting trials, though the improvement was greatest on the exercise trial. However, response times only improved on the resting trial following the high GI breakfast (p=0.012). On the 5 letter level of the Sternberg paradigm, response times improved across the morning following the low GI breakfast (regardless of exercise) and only on the exercise trial following the high GI breakfast (p=0.019). The findings of the present study suggest that the combined effects of breakfast GI and exercise in adolescents depend upon the component of cognitive function examined. A low GI breakfast and mid-morning bout of exercise were individually beneficial for response times on the Sternberg paradigm, whereas they conferred additional benefits for response times on the Stroop test., (Copyright © 2014 Elsevier Inc. All rights reserved.)

We investigated the cognitive effects of exercising in the heat on the field players of two football teams in a series of three matches. Different rehydration and cooling strategies were used for one of the teams during the last two games. Cognitive functions were measured before, during and immediately after each football match, as well as core temperature, body mass, plasma osmolality and glucose levels, allowing an estimate of their differential impacts on cognition. The pattern of results suggests that mild-moderate dehydration during exercise in the heat (up to 2.5%) has no clear effect on cognitive function. Instead, plasma glucose and core temperature changes appear to be the main determinants: higher glucose was related to faster and less accurate performance, whereas core temperature rises had the opposite effect. The 50% correlation between plasma glucose and core temperatures observed during exercise in the heat may help to stabilize cognitive performance via their opposing effects. The glucose-like effects of sports drinks appear to be mediated by increased plasma glucose levels, because drinks effects became non-significant when plasma glucose levels were added to the models. The cooling intervention had only a beneficial effect on complex visuo-motor speed. [ABSTRACT FROM AUTHOR]