Adolescence (ages 13–18 years) is a period of significant growth and physical development that includes changes in body composition, metabolic and hormonal fluctuations, maturation of organ systems, ...and establishment of nutrient deposits, which all may affect future health. In terms of nutrition, adolescence is also an important time in establishing an individual’s lifelong relationship with food, which is particularly important in terms of the connection between diet, exercise, and body image. The challenges of time management (e.g., school, training, work and social commitments) and periods of fluctuating emotions are also features of this period. In addition, an adolescent’s peers become increasingly powerful moderators of all behaviours, including eating. Adolescence is also a period of natural experimentation and this can extend to food choice. Adolescent experiences are not the same and individuals vary considerably in their behaviours. To ensure an adolescent athlete fulfils his/her potential, it is important that stakeholders involved in managing youth athletes emphasize eating patterns that align with and support sound physical, physiological and psychosocial development and are consistent with proven principles of sport nutrition.
Inadequate sleep (i.e., duration and/or quality) is becoming increasingly recognized as a global public health issue. Interaction via the gut-brain axis suggests that modification of the gut ...microbial environment via supplementation with live microorganisms (probiotics) or nonviable microorganisms/microbial cell fractions (paraprobiotics) may improve sleep health. This systematic review and meta-analysis aimed to clarify the effect of consuming probiotics/paraprobiotics on subjective and objective sleep metrics. Online databases were searched from 1980 to October 2019 for studies involving adults who consumed probiotics or paraprobiotics in controlled trials, during which, changes in subjective and/or objective sleep parameters were examined. A total of 14 studies (20 trials) were included in meta-analysis. Random effects meta-analyses indicated that probiotics/paraprobiotics supplementation significantly reduced Pittsburgh Sleep Quality Index (PSQI) score (i.e., improved sleep quality) relative to baseline (-0.78-points, 95% confidence interval: 0.395-1.166; p < 0.001). No significant effect was found for changes on other subjective sleep scales, nor objective parameters of sleep (efficiency/latency) measured using polysomnography or actigraphy. Subgroup analysis for PSQI data suggested that the magnitude of the effect was greater (although not statistically) in healthy participants than those with a medical condition, when treatment contained a single (rather than multiple) strain of probiotic bacteria, and when the duration of treatment was ≥8 weeks. Probiotics/paraprobiotics supplementation may have some efficacy in improving perceived sleep health, measured using the PSQI. While current evidence does not support a benefit of consuming probiotics/paraprobiotics when measured by other subjective sleep scales, nor objective measures of sleep; more studies using well-controlled, within-subject experimental designs are needed.
•SDLP is a sensitive measure of alcohol-impaired driving in simulator studies.•Regression analysis predicts that SDLP increases from as low as 21mg·dL−1 BAC.•SDLP increases by 0.7cm for every ...10mg·dL−1 increase in BAC thereafter.
Driving simulators are used in a wide range of research settings to help develop an understanding of driver behavior in complex environments. Acute alcohol impairment is an important research topic for traffic safety and a large number of studies have indicated levels of simulated driving impairment imposed by alcohol across a range of performance outcome variables. The aim of the present study was to examine the impact of acute alcohol consumption on simulated driving performance by conducting a systematic review and meta-analysis of the available evidence. The online databases PubMed (MEDLINE), Web of Science (via Thomas Reuters) and Scopus were searched to identify studies that measured simulated car driving performance under control ('no alcohol' or ‘placebo alcohol’ ingestion) and intervention (acute alcohol ingestion) conditions, using repeated-measures experimental designs. Primary research outcomes were standard deviation of lane position (SDLP) and standard deviation of speed (SDSP); (total number of lane crossings (LC) and average speed (Speed) were secondary research outcomes). Meta-analytic procedures were used to quantify the effect of acute alcohol consumption on vehicle control, and to determine the influence of methodological variables (i.e. the duration of the simulated driving task, the limb of the BAC curve (ascending vs. descending) and the type of driving simulator employed (i.e. car vs. PC-based)) on the magnitude of the performance change due to alcohol consumption. 423 records were screened, and 50 repeated-measures trials (n=962 participants, 62% male) derived from 17 original publications were reviewed. 37 trials (n=721 participants) used a ‘placebo alcohol’ comparator to determine the effect of alcohol consumption on SDLP (32/37) and SDSP (22/37). Alcohol consumption significantly increased SDLP by 4.0±0.5cm (95% CI: 3.0, 5.1) and SDSP by 0.38±0.10km⋅h−1 (95% CI: 0.19, 0.57). Regression analyses indicate BAC (p=0.004) and driving simulator platform (p<0.001) influence the magnitude of the SDLP change, such that higher BAC levels and the use of PC-based driving simulators were associated with larger performance decrements (R2=0.80). The limb of the BAC curve and the duration of the driving task did not significantly alter the magnitude of the performance change. Eleven trials (n=205 participants) used a ‘no alcohol’ comparator to measure the effect of alcohol consumption on SDLP (10/11); few trials assessed SDSP (3/11). Alcohol consumption resulted in a small significant increase in SDLP under these conditions (standardized difference in means=0.23, 95% CI: 0.06, 0.39). These results demonstrate that lateral (SDLP and LC) and longitudinal (SDSP) vehicle control measures in a driving simulator are impaired with acute alcohol consumption. However, SDLP appears to be a more sensitive indicator of driving impairment than other driving performance variables and the results of the present study support its use as a performance outcome when examining alcohol-induced simulated driving impairment.
Background
Sleep loss may influence subsequent physical performance. Quantifying the impact of sleep loss on physical performance is critical for individuals involved in athletic pursuits.
Design
...Systematic review and meta-analysis.
Search and Inclusion
Studies were identified via the Web of Science, Scopus, and PsycINFO online databases. Investigations measuring exercise performance under ‘control’ (i.e., normal sleep, > 6 h in any 24 h period) and ‘intervention’ (i.e., sleep loss, ≤ 6 h sleep in any 24 h period) conditions were included. Performance tasks were classified into different exercise categories (anaerobic power, speed/power endurance, high-intensity interval exercise (HIIE), strength, endurance, strength-endurance, and skill). Multi-level random-effects meta-analyses and meta-regression analyses were conducted, including subgroup analyses to explore the influence of sleep-loss protocol (e.g., deprivation, restriction, early delayed sleep onset and late restriction earlier than normal waking), time of day the exercise task was performed (AM vs. PM) and body limb strength (upper vs. lower body).
Results
Overall, 227 outcome measures (anaerobic power:
n
= 58; speed/power endurance:
n
= 32; HIIE:
n
= 27; strength:
n
= 66; endurance:
n
= 22; strength-endurance:
n
= 9; skill:
n
= 13) derived from 69 publications were included. Results indicated a negative impact of sleep loss on the percentage change (%
Δ
) in exercise performance (
n
= 959 89% male; mean %
Δ
= − 7.56%, 95% CI − 11.9 to − 3.13,
p
= 0.001,
I
2
= 98.1%). Effects were significant for all exercise categories. Subgroup analyses indicated that the pattern of sleep loss (i.e., deprivation, early and late restriction) preceding exercise is an important factor, with consistent negative effects only observed with deprivation and late-restriction protocols. A significant positive relationship was observed between time awake prior to the exercise task and %
Δ
in performance for both deprivation and late-restriction protocols (~ 0.4% decrease for every hour awake prior to exercise). The negative effects of sleep loss on different exercise tasks performed in the PM were consistent, while tasks performed in the AM were largely unaffected.
Conclusions
Sleep loss appears to have a negative impact on exercise performance. If sleep loss is anticipated and unavoidable, individuals should avoid situations that lead to experiencing deprivation or late restriction, and prioritise morning exercise in an effort to maintain performance.
Facebook is a popular platform that may facilitate learning activities at university. In this study, students' perceptions of using 'Facebook pages' within individual university subject offerings ...were evaluated. Individual 'Facebook pages' were developed for four university courses at Griffith University's gold Coast campus and used to provide information relevant to the courses and allow opportunities for student interaction. An initial questionnaire administered in the first lecture of semester indicated that nearly all students (n=161, 93.1%) possessed an active Facebook account. Most students (n=135, 78.0%) anticipated that a Facebook page would facilitate their learning, by increased interaction with students and instructors, and notifications for course information. A second questionnaire was completed in the final lecture of semester indicating that 81.9% of students engaged with the course Facebook page at some stage. However, perceptions of the effectiveness of the page as a learning tool were variable, with only 51% of students stating that it was effective. Despite this, the majority of students (n=110, 76.4%) recommended using Facebook in future courses. This preliminary evaluation of Facebook as a learning aid suggests that it has the potential to promote collaborative and cooperative learning, but further research is required, specifically to understand if and how it can enhance learning outcomes. Author abstract, ed
Understanding of the impact of an acute bout of exercise on hormones involved in appetite regulation may provide insight into some of the mechanisms that regulate energy balance. In resting ...conditions, acylated ghrelin is known to stimulate food intake, while hormones such as peptide YY (PYY), pancreatic polypeptide (PP) and glucagon-like peptide 1 (GLP-1) are known to suppress food intake.
The objective of this review was to determine the magnitude of exercise effects on levels of gastrointestinal hormones related to appetite, using systematic review and meta-analysis. Additionally, factors such as the exercise intensity, duration and mode, in addition to participant characteristics, were examined to determine their influence on these hormones.
Major databases (PubMed, Scopus, Google Scholar, Science Direct, Academic Search Premier and EBSCOHost) were searched, through February 2013, for original studies, abstracts, theses and dissertations that examined responses of appetite hormones to acute exercise.
Studies were included if they evaluated appetite hormone responses during and in the hours after an acute bout of exercise and reported area under the concentration-time curve (AUC) values for more than three datapoints. Studies reporting mean or pre/post-values only were excluded.
Initially, 75 studies were identified. After evaluation of study quality and validity, using the Physiotherapy Evidence Database scale, data from 20 studies (28 trials) involving 241 participants (77.6 % men) had their data extracted for inclusion in the meta-analyses. A random-effects meta-analysis was conducted for acylated ghrelin (n = 18 studies, 25 trials) and PYY (n = 8 studies, 14 trials), with sub-group analyses and meta-regressions being conducted for moderator variables. Because the number of studies was limited, fixed-effects meta-analyses were performed on PP data (n = 4 studies, 5 trials) and GLP-1 data (n = 5 studies, 8 trials).
The results of the meta-analyses indicated that exercise had small to moderate effects on appetite hormone levels, suppressing acylated ghrelin (effect size ES Cohen's d value -0.20, 95 % confidence interval CI -0.373 to -0.027; median decrease 16.5 %) and increasing PYY (ES 0.24, 95 % CI 0.007 to 0.475; median increase 8.9 %), GLP-1 (ES 0.275, 95 % CI -0.031 to 0.581; median increase 13 %), and PP (ES 0.50, 95 % CI 0.11 to 0.89; median increase 15 %). No significant heterogeneity was detected in any meta-analysis (using Cochrane's Q and I (2)); however, publication biases were detected for all analyses. No moderator variables were observed to moderate the variability among the studies assessing acylated ghrelin and PYY.
The majority of the present literature is acute in nature; therefore, longer-term alterations in appetite hormone concentrations and their influence on food and beverage intake are unknown. Furthermore, our review was limited to English-language studies and studies reporting AUC data.
An acute bout of exercise may influence appetite by suppressing levels of acylated ghrelin while simultaneously increasing levels of PYY, GLP-1 and PP, which may contribute to alterations in food and drink intake after acute exercise. Further longitudinal studies and exploration into mechanisms of action are required in order to determine the precise role these hormones play in long-term appetite responses to an exercise intervention.
Abstract Objective The aim of this study was to examine the association between dietary supplement use and sociodemographic factors in an Australian university population. Additionally, reasons for ...use of specific dietary supplements were explored. Methods A cross-sectional online questionnaire was completed by 1633 students and staff members of Griffith University, Queensland, Australia (76% female). The questionnaire collected information on sociodemographic characteristics, use of dietary supplements, and reasons for use of each dietary supplement reported. Multiple regression analyses were used to describe the relationship between demographic factors and dietary supplement use. Pearson χ2 was used to identify correlations between frequency of dietary supplement use and selected demographic factors. Frequency distributions were used to explore the reasons for use of each dietary supplement reported. Results Vitamin or mineral use and use of “other” dietary supplements was reported by 69% and 63% of participants, respectively. Age, sex, ethnicity, and physical activity were independently associated with dietary supplement use. Age, sex, and income were associated with acute use of specific dietary supplements during illness or injury. The reasons for use of specific dietary supplements were closely aligned with marketed claims. Broad reasons of health were commonly reported for use of most dietary supplements. Conclusions Use of dietary supplements in this population reflects that of other countries. Individuals were unsure of the benefits and risks associated with dietary supplementation. Health professionals should account for dietary supplements when assessing diet. These results also warrant consideration by regulating bodies and public health officers to ensure safe practices.
Abstract Objective Nutrition is an important part of patients’ recovery in hospital. This study assessed the nutritional adequacy of meals provided to and consumed by patients prescribed a ...therapeutic diet. Research Methods & Procedures: Patients (n=110) prescribed a therapeutic diet (texture modified, low fibre, oral fluid or food allergy/intolerance diets) for medical or nutritional reasons were recruited from six wards of a tertiary hospital. Complete (24hr) dietary provisions and intakes were directly observed and analysed for energy (kJ) and protein (g) content. A chart audit gathered demographic, clinical and nutrition-related information to calculate each patient's disease-specific estimated energy and protein requirements. Provisions and intakes were considered adequate if they met ≥75% of patients' estimated requirements. Results Mean energy and protein provided to patients (5844±2319kJ, 53±30g) were significantly lower than their mean estimated requirements (8786±1641kJ, 86±18g). Consequently, mean nutrition intakes (4088±2423kJ, 37±28g) were significantly lower than estimated requirements. Only 37% (n=41) of patients were provided with and 18% (n=20) consumed adequate nutrition to meet their estimated requirements. No therapeutic diet provided adequate food to meet the energy and protein requirements of all recipients. Patients on oral fluid diets had the highest estimated requirements (9497±1455kJ, 93±16g) and the lowest nutrient provision (3497±1388kJ, 25±19g) and intake (2156±1394kJ, 14±14g). Conclusion Hospitalised patients prescribed therapeutic diets (particularly fluid only diets) are at risk of malnutrition. Further research is required to determine the most effective strategies to improve nutritional provision and intake among patients prescribed therapeutic diets.
Timely and adequate nutrition after surgery is important. The aim of this study was to evaluate the effects of an intervention, developed using an integrated knowledge translation approach, designed ...to improve oral intake among postoperative colorectal patients.
A pre/post, mixed-methods pilot study was undertaken at a tertiary teaching hospital in Australia. Patients who had undergone elective colorectal surgery and were admitted to the ward where 10 nutrition-related strategies had been implemented were included. Quantitative data, including patient demographics, timing and type of nutrition consumed, and protein and energy intake were collected pre- and post-intervention via chart audits, direct observations, and verbal clarification. Qualitative data on patient (n = 18) responses to the intervention were collected through one-on-one, semistructured interviews and analyzed using inductive content analysis.
Sixty-four patients were observed (30 pre- and 34 post-intervention). Significant improvements were seen for the following outcomes (presented as median interquartile range, pre- versus post-intervention): time (h) to first dietary intake (15.7 7.4–22.5 versus 4.9 3.7–14.2); patient energy intakes (kJ) on day 1 (1719 947–2200 versus 3530 2192–5169) and day 2 (2506 1071–3749 versus 4144 2987–5889); and patient protein intake (g) on day 1 (3.3 1.8–11.2 versus 30.3 20–45) and day 2 (10.8 3.5–29.9 versus 39.6 30.7–59). Prescription of free fluids as first diet type increased from 13% to 79% pre- and post-intervention, respectively. There were no significant differences in time (h) to first solid dietary intake (86.1 60.1–104 versus 69.2 46.1–115.5) and overall proportion of patients who met both their estimated energy and protein requirements while in hospital pre- and post-intervention (22 versus 37%). Patients reported positive experiences with the intervention.
A multifaceted intervention developed using an integrated knowledge translation approach has the potential to improve oral intake in patients who undergo colorectal surgery. A larger-scale trial is required to confirm these findings and assess the effects of the intervention on clinical outcomes and costs.
•An integrated knowledge translation intervention can improve oral intake in postoperative colorectal patients.•Time to first oral prescription, delivery, and intake improved.•Oral intake for the first 2 d after surgery improved.•Prescription of free fluids (versus clear fluids) as first diet type improved.•Patients reported positive experiences with the intervention but suggested improvements.
Gastric emptying (GE) could influence exercise-induced changes in appetite and energy intake. GE also could contribute to changes in gastric symptoms and the availability of nutrients during ...exercise, which will subsequently affect performance.
The objective of this review was to determine the effects of acute exercise on GE using a systematic review and meta-analysis. The most common parameters to determine GE were selected, consisting of half-emptying time and volume emptied. Oral-caecal transit time (OCTT) was also examined.
Research databases (PubMed, Scopus, Google Scholar, EBSCOhost, SPORTDiscus) were searched through November 2013 for original studies, abstracts, theses and dissertations that examined the influence of acute exercise on GE.
Studies were included if they evaluated GE or OCTT during and/or after exercise and involved a resting control trial.
Initially, 195 studies were identified. After evaluation of study characteristics and quality and validity, data from 20 studies (35 trials) involving 221 participants (157 men; 52 women; 12 unknown) were extracted for meta-analysis. Random-effects meta-analyses were utilised for the three main outcome variables, and effect sizes (ES) are reported as Hedge's g due to numerous small sample sizes.
Random-effects modelling revealed non-significant and small/null main effect sizes for volume emptied (ES = 0.195; 95% CI -0.25 to 0.64), half-time (ES = -0.109, 95% CI -0.66 to 0.44) and OCTT (ES = 0.089; 95% CI -0.64 to 0.82). All analyses exhibited significant heterogeneity and numerous variables moderated the results. There was a dose response of exercise intensity; at lower intensities GE was faster, and at high exercise intensities GE was slower. Walking was associated with faster GE and cycling with slower GE. Greater volume of meal/fluid ingested, higher osmolality of beverage and longer exercise duration were also associated with slower GE with exercise.
The major limitation is that the majority of studies utilised a liquid bolus administered pre-exercise to determine GE; the relationship to post-exercise appetite and energy intake remains unknown. Study populations were also generally active or trained individuals. Furthermore, our review was limited to English language studies and studies that utilised resting control conditions.
These results suggest that exercise intensity, mode, duration and the nature of meal/fluid ingested all influence GE during and after acute exercise. The relationship of GE parameters with appetite regulation after exercise remains largely unexplored. Further integrative studies combining GE and alterations in gut hormones, as well as in populations such as overweight and obese individuals are needed.
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