Assessment of dietary nitrate supplementation: prevalence of use, knowledge, attitudes and beliefs among active Australians.

Introduction: Use of nitrate as a dietary supplement has gained popularity among athletes and recreationally active individuals to enhance exercise performance. However, the prevalence and patterns of use, and knowledge of nitrate as a dietary supplement are unknown. Methods: Individuals (≥16y) completed a 42-item online questionnaire to collect (i) sociodemographic information; (ii) participation in activity and sport; (iii) nitrate supplementation use and reasons; (iv) attitudes and beliefs regarding information sources and the safety of nitrate as a dietary supplement; and (v) knowledge of dietary nitrate supplements. Results: In total, 1,404 active adults (66% female) took part in the study. Only about one in 10 respondents (11.9%) reported they had consumed dietary nitrate ("users") in the past, most commonly as beetroot juice (31.3%). Over two-thirds (69.4%) of users could not correctly identify the correct timing of intake relative to performance time to best improve exercise performance, and most users (82.3%) were unsure of the contraindications to oral consumption of dietary nitrate supplements. Only 3.9% of users experienced adverse effects after ingesting dietary nitrate supplements. Among non-users, the most common reasons respondents selected for not using dietary nitrate supplements were "I do not think I need to" (70.2%) and "I have never thought about it" (69.2%). Discussion: There is evidence to support the efficacy of dietary nitrate intake in improving exercise performance. However, findings from this study suggest dietary nitrate is under-utilized. Educational messages that target dietary nitrate consumption should be targeted toward nutritionists, coaches, and exercise physiologists to bridge the gap between knowledge-to-practice.

Estimating nitrate intake in the Australian diet: Design and validation of a food frequency questionnaire.

BACKGROUND: Dietary nitrates may play a role in mediating several key physiological processes impacting health and/or exercise performance. However, current methods for assessing dietary nitrate (NO3 - ) consumption are inadequate. The present study aimed to examine the dietary nitrate intake in a sample of 50 healthy adults, as well as test the validity of a purposefully developed food frequency questionnaire (FFQ). METHODS: Dietary nitrate intake was estimated over a week using (i) three 24-h dietary recalls; (ii) a short-term (7-day) FFQ; and (iii) a biomarker (urinary nitrate), in conjunction with a nitrate reference database. RESULTS: Daily dietary nitrate intake estimates were 130.94 mg (average of three 24-h recalls) and 180.62 mg (FFQ). The mean urinary NO3 - excretion was 1974.79 µmol day-1 (or 917.9 µmol L-1 ). Despite the difference between the two dietary assessment methods, there was a moderate positive correlation (r = 0.736, ρ < 0.001) between the two tools. There was also a positive correlation between urinary NO3 - and 24-h recall data (r = 0.632, ρ < 0.001), as well as between urinary NO3 - and FFQ (r = 0.579, ρ < 0.001). CONCLUSIONS: The ability to accurately estimate nitrate intakes depends on having suitable reference methods to estimate the concentrations of nitrate in the food supply, coupled with valid and reliable dietary assessment tools. Based on the findings from the present study, at an individual level, dietary recalls or records may be more accurate in estimating intakes of NO3 - . However, given the lower cost and time needed for administration relative to recalls, the FFQ has merit for estimating NO3 - intakes in health interventions, dietary surveys and surveillance programs.

The efficacy of morning versus evening exercise for weight loss: A randomized controlled trial.

OBJECTIVE: The aim of this study was to investigate the influence of morning versus evening exercise on weight loss, cardiometabolic health, and components of energy balance. METHODS: A total of 100 inactive adults with overweight or obesity were randomized to morning exercise (AMEx; 06:00-09:00), evening exercise (PMEx; 16:00-19:00), or wait-list control (CON). AMEx and PMEx were prescribed 250 min·wk-1 of self-paced aerobic exercise for 12 weeks. Anthropometry and body composition, physical activity, and dietary intake were assessed at baseline, 6 weeks, and 12 weeks. Cardiorespiratory fitness (V̇O2 peak), resting metabolic rate, and blood markers were assessed at baseline and 12 weeks. Body composition and V̇O2 peak were also measured at 3- and 6-month follow-up. RESULTS: AMEx and PMEx lost weight during the intervention (mean [SD], AMEx, -2.7 [2.5] kg, p < 0.001; PMEx, -3.1 [3.4] kg, p < 0.001). V̇O2 peak significantly increased in both intervention groups, and these changes were different from CON (AMEx, +4.7 mL·kg-1 ·min-1 , p = 0.034; PMEx, +4.2 mL·kg-1 ·min-1 , p = 0.045). There were no between-group differences for resting metabolic rate or physical activity. At 12 weeks, total energy intake was significantly reduced in both AMEx and PMEx versus CON (AMEx, -3974 kJ, p < 0.001; PMEx, -3165 kJ, p = 0.001). CONCLUSIONS: Adults with overweight and obesity experience modest weight loss in response to an exercise program, but there does not appear to be an optimal time to exercise.

How do previously inactive individuals restructure their time to 'fit in' morning or evening exercise: a randomized controlled trial.

The objective of this study was to investigate changes in sedentary and active behaviors when previously inactive adults start exercising in the morning or evening. One-hundred adults with overweight or obesity (BMI ≥ 25 kg/m2) were recruited for a 12-week intervention and randomized to one of three groups: (i) morning exercise (AMEx; 0600-0900); (ii) evening exercise (PMEx; 1600-1900); or (iii) waitlist control. AMEx and PMEx were prescribed self-paced aerobic exercise to achieve a weekly total of 250 min via a combination of supervised and unsupervised training. Sedentary and active behavior times were measured at baseline, mid- and post-intervention using the multimedia activity recall for children and adults. Time spent engaging in physical activity was significantly increased from baseline at both mid- (+ 14-22 min·day-1) and post-intervention (+ 12-19 min·day-1), for AMEx and PMEx. At 12-weeks, participants in both morning and evening exercise groups reported increased time spent Sleeping (+ 36 and + 20 min·day-1, respecitively), and reduced time spent watching TV/playing videogames (- 32 and - 25 min·day-1, respectively). In response to an exercise stimulus, previously inactive adults make encouraging modifications in how they use their time, and the patterns of change are similar with morning and evening exercise.

Nitrate, nitrite and nitrosamines in the global food supply.

Inorganic nitrate provided by either nitrate salts or food supplements may improve cardiometabolic health. However, current methods to assess dietary nitrate, nitrite and nitrosamine consumption are inadequate. The purpose of this study was to develop a reference database to estimate the levels of nitrate, nitrite and nitrosamines in the global food supply. A systematic literature search was undertaken; of the 5,747 articles screened, 448 met the inclusion criteria. The final database included data for 1,980 food and beverages from 65 different countries. There were 5,105 unique records for nitrate, 2,707 for nitrite, and 954 for nitrosamine. For ease of use, data were sorted into 12 categories; regarding nitrate and nitrite concentrations in food and beverages, 'vegetables and herbs' were most reported in the literature (n = 3,268 and n = 1,200, respectively). For nitrosamines, 'protein foods of animal origin' were most reported (n = 398 records). This database will allow researchers and practitioners to confidently estimate dietary intake of nitrate, nitrite and nitrosamines. When paired with health data, our database can be used to investigate associations between nitrate intake and health outcomes, and/or exercise performance and could support the development of key dietary nitrate intake guidelines.

Does the Time-of-Day of Exercise Influence the Total Volume of Exercise? A Cross-Sectional Analysis of Objectively Monitored Physical Activity Among Active Individuals.

BACKGROUND: To improve compliance and adherence to exercise, the concept of temporal consistency has been proposed. Before- and after-work are periods when most working adults may reasonably incorporate exercise into their schedule. However, it is unknown if there is an association between the time-of-day that exercise is performed and overall physical activity levels. METHODS: Activity was assessed over 1 week in a sample of 69 active adults (n = 41 females; mean age = 34.9 [12.3] y). At the end of the study, participants completed an interviewer-assisted questionnaire detailing their motivation to exercise and their exercise time-of-day preferences. RESULTS: Participants were classified as "temporally consistent" (n = 37) or "temporally inconsistent" (n = 32) exercisers based on their accelerometry data. The "temporally consistent" group was further analyzed to compare exercise volume between "morning-exercisers" (n = 16) and "evening-exercisers" (n = 21). "Morning-exercisers" performed a greater volume of exercise than "evening-exercisers" (419 [178] vs 330 [233] min by self-report; 368 [224] vs 325 [156] min actigraph-derived moderate to vigorous physical activity, respectively). CONCLUSIONS: Our findings suggest that active individuals use a mixture of temporal patterns to meet PA guidelines. Time-of-day of exercise should be reported in intervention studies so the relationship between exercise time-of-day, exercise behavior, and associated outcomes can be better understood.

High intensity interval training does not result in short- or long-term dietary compensation in cardiac rehabilitation: Results from the FITR heart study.

The aim of this study was to investigate short- and long-term compensatory effects on dietary intake following high intensity interval training (HIIT) compared with usual care moderate intensity continuous training (MICT) during and following a cardiac rehabilitation program. This study investigates secondary outcomes of a clinical trial. Ninety-three participants with coronary artery disease enrolled in a 4-week cardiac rehabilitation program, were randomised to 1) 4x4-minute HIIT; or 2) 40-min of MICT (usual care). Patients were instructed to complete 3 weekly sessions (2 supervised, 1 home-based) for 4-weeks, and 3 weekly home-based sessions thereafter for another 48-weeks. Dietary intake was measured by telephone-based 24-h recall over 2 day at baseline, 4-weeks, 3-months, 6-months, and 12-months. Three-Factor Eating Questionnaire was used to measure dietary behaviour and Leeds Food Preference Questionnaire used to measure food preferences. Appetite was assessed by a visual analogue scale and appetite-regulating hormones. There was no change over the study period or differences between groups for daily energy intake at 4-weeks or 12-months. There were also no group differences for any other measures of dietary intake, fasting hunger or appetite-related hormones, dietary behaviour, or food preferences. These findings suggest that compared to moderate intensity exercise, HIIT does not result in compensatory increases of energy intake or indicators of poor diet quality. This finding appears to be the same for patients with normal weight and obesity. HIIT can therefore be included in cardiac rehabilitation programs as an adjunct or alterative to MICT, without concern for any undesirable dietary compensation.

Short-term and Long-term Feasibility, Safety, and Efficacy of High-Intensity Interval Training in Cardiac Rehabilitation: The FITR Heart Study Randomized Clinical Trial.

Importance: High-intensity interval training (HIIT) is recognized as a potent stimulus for improving cardiorespiratory fitness (volume of oxygen consumption [VO2] peak) in patients with coronary artery disease (CAD). However, the feasibility, safety, and long-term effects of HIIT in this population are unclear. Objective: To compare HIIT with moderate-intensity continuous training (MICT) for feasibility, safety, adherence, and efficacy of improving VO2 peak in patients with CAD. Design, Setting, and Participants: In this single-center randomized clinical trial, participants underwent 4 weeks of supervised training in a private hospital cardiac rehabilitation program, with subsequent home-based training and follow-up over 12 months. A total of 96 participants with angiographically proven CAD aged 18 to 80 years were enrolled, and 93 participants were medically cleared for participation following a cardiopulmonary exercise test. Data were collected from May 2016 to December 2018, and data were analyzed from December 2018 to August 2019. Interventions: A 4 × 4-minute HIIT program or a 40-minute MICT program (usual care). Patients completed 3 sessions per week (2 supervised and 1 home-based session) for 4 weeks and 3 home-based sessions per week thereafter for 48 weeks. Main Outcomes and Measures: The primary outcome was change in VO2 peak during the cardiopulmonary exercise test from baseline to 4 weeks. Further testing occurred at 3, 6, and 12 months. Secondary outcomes were feasibility, safety, adherence, cardiovascular risk factors, and quality of life. Results: Of 93 randomized participants, 78 (84%) were male, the mean (SD) age was 65 (8) years, and 46 were randomized to HIIT and 47 to MICT. A total of 86 participants completed testing at 4 weeks for the primary outcome, including 43 in the HIIT group and 43 in the MICT group; 69 completed testing at 12 months for VO2 peak, including 32 in the HIIT group and 37 in the MICT group. After 4 weeks, HIIT improved VO2 peak by 10% compared with 4% in the MICT group (mean [SD] oxygen uptake: HIIT, 2.9 [3.4] mL/kg/min; MICT, 1.2 [3.4] mL/kg/min; P = .02). After 12 months, there were similar improvements from baseline between groups, with a 10% improvement in the HIIT group and a 7% improvement in the MICT group (mean [SD] oxygen uptake: HIIT, 2.9 [4.5] mL/kg/min; MICT, 1.8 [4.3] mL/kg/min; P = .30). Both groups had high feasibility scores and low rates of withdrawal due to serious adverse events (3 participants in the HIIT group and 1 participant in the MICT group). One event occurred following exercise (hypotension) in the HIIT group. Over 12 months, both home-based HIIT and MICT had low rates of adherence (HIIT, 18 of 34 [53%]; MICT, 15 of 37 [41%]; P = .35) compared with the supervised stage (HIIT, 39 of 44 [91%]; MICT, 39 of 43 [91%]; P > .99). Conclusions and Relevance: In this randomized clinical trial, a 4-week HIIT program improved VO2 peak compared with MICT in patients with CAD attending cardiac rehabilitation. However, improvements in VO2 peak at 12 months were similar for both groups. HIIT was feasible and safe, with similar adherence to MICT over 12-month follow-up. These findings support inclusion of HIIT in cardiac rehabilitation programs as an adjunct or alternative modality to moderate-intensity exercise. Trial Registration: Australian New Zealand Clinical Trials Registry Identifier: ACTRN12615001292561.

Effect of High-Intensity Interval Training on Visceral and Liver Fat in Cardiac Rehabilitation: A Randomized Controlled Trial.

OBJECTIVE: This study aimed to investigate the effect of exercise intensity on visceral adipose tissue (VAT) and liver fat reduction in patients with coronary artery disease (CAD) over 3 months and the maintenance of improvements over 12 months. METHODS: Forty-two participants with CAD were randomized to three sessions/week of either 4 × 4-minute high-intensity interval training (HIIT) or 40 minutes of usual care moderate-intensity continuous training (MICT) for a 4-week supervised cardiac rehabilitation program, followed by three home-based sessions/week for 11 months. Liver fat (as intrahepatic lipid) and VAT were measured via magnetic resonance techniques. Data are mean change (95% CI). RESULTS: HIIT and MICT significantly reduced VAT over 3 months (-350 [-548 to -153] cm3 vs. -456 [-634 to -278] cm3 ; time × group effect: P = 0.421), with further improvement over 12 months (-545 [-818 to -271] cm3 vs. -521 [-784 to -258] cm3 ; time × group effect: P = 0.577) and no differences between groups. Both groups improved liver fat over 3 months, with HIIT tending to show greater reduction than MICT (-2.8% [-4.0% to -1.6%] vs. -1.4% [-2.4% to -0.4%]; time × group effect: P = 0.077). After 12 months, improvements were maintained to a similar degree. Higher exercise intensity predicted liver fat reduction (ß = -0.3 [-0.7 to 0.0]; P = 0.042). CONCLUSIONS: HIIT and MICT reduced VAT over 3 and 12 months. For liver fat, HIIT tended to provide a slightly greater reduction compared with MICT. These findings support HIIT as a beneficial adjunct or alternative to MICT for reducing visceral and liver fat in patients with CAD.

The feasibility and acceptability of morning versus evening exercise for overweight and obese adults: A randomized controlled trial.

BACKGROUND: The time of day that people exercise could have an influence on the efficacy of exercise for weight loss, via differences in adherence and/or physiological adaptations. However, there is currently no evidence to support an optimal time of day for exercise to maximise efficacy. PURPOSE: To examine the feasibility and acceptability of prescribed morning and evening exercise. METHODS: Twenty inactive, overweight adults aged 18-60 years were recruited for a 12-week intervention and randomized to one of three groups using a 2:2:1 random allocation ratio: i) morning exercise (AM; n = 9); ii) evening exercise (PM; n = 7); or iii) waitlist control (CON; n = 4). Exercise groups were prescribed self-paced walking or running on a treadmill to achieve a weekly total of 250 min. Feasibility and acceptability data were collected, and physiological and behavioural outcomes associated with energy balance were measured at baseline, mid- and post-intervention. RESULTS: Attrition was low (n = 2 dropped out), with high measurement completion rates (>80%). The intervention groups had high adherence rates to exercise sessions (94% and 87% for the AM and PM groups, respectively). No adverse events resulting from the intervention were reported. Both intervention groups displayed improvements to their cardiometabolic risk profile; cardiorespiratory fitness improved by 5.2 ±â€¯4.7, and 4.6 ±â€¯4.5 mL kg-1.min-1 and body fat percentage reduced by 1.2 ±â€¯1.4, and -0.6 ±â€¯1.2% for AM and PM groups, respectively. CONCLUSION: This feasibility study provides evidence that morning and evening exercise interventions are feasible, and also provides justification for a large-scale randomized controlled trial. TRIAL REGISTRATION: This trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616000457448p, 7/4/2016).

Women Experience the Same Ergogenic Response to Caffeine as Men.

PURPOSE: This study aimed to determine whether 1) consumption of caffeine improves endurance cycling performance in women and 2) sex differences exist in the magnitude of the ergogenic and plasma responses to caffeine supplementation. METHODS: Twenty-seven (11 women and 16 men) endurance-trained cyclists and triathletes participated in this randomized, double-blind, placebo-controlled, crossover study. Participants completed an incremental exercise test to exhaustion, two familiarization trials, and two performance trials. Ninety minutes before the performance trials, participants ingested opaque capsules containing either 3 mg·kg body mass of anhydrous caffeine or a placebo. They then completed a set amount of work (75% of peak sustainable power output) in the fastest possible time. Plasma was sampled at baseline, preexercise, and postexercise for caffeine. Strict standardization and verification of diet, hydration, training volume and intensity, and contraceptive hormone phase (for women) were implemented. RESULTS: Performance time was significantly improved after caffeine administration in women (placebo: 3863 ± 419 s, caffeine: 3757 ± 312 s; P = 0.03) and men (placebo: 3903 ± 341 s, caffeine: 3734 ± 287 s; P < 0.001). The magnitude of performance improvement was similar for women (mean = 4.3%, 95% CI = 0.4%-8.2%) and men (4.6%, 2.3%-6.8%). Plasma caffeine concentrations were similar between sexes before exercise, but significantly greater in women after exercise (P < 0.001). CONCLUSIONS: Ingestion of 3 mg·kg body mass of caffeine enhanced endurance exercise performance in women. The magnitude of the performance enhancement observed in women was similar to that of men, despite significantly greater plasma caffeine concentrations after exercise in women. These results suggest that the current recommendations for caffeine intake (i.e., 3-6 mg·kg caffeine before exercise to enhance endurance performance), which are derived almost exclusively from studies on men, may also be applicable to women.

Physical profiles of elite, sub-elite, regional and age-group netballers.

Physical profile data from elite, sub-elite, regional, under 21s (U21), under 19s (U19) and under 17s (U17) (n = 845) players from a state netball association in Australia were analysed. Within season changes were examined for the elite and sub-elite players. Longitudinal changes were examined for the elite across four consecutive netball seasons. Elite were significantly older (24.3 ± 3.4years), taller (182.4 ± 7.2cm) and heavier (73.42 ± 6.95kg) than other playing levels (p < 0.001, ES 0.49-3.26) and had higher vertical jump (VJ) data compared to all groups (p < 0.001, ES 0.47-0.93). U17's were significantly faster than elite, sub-elite and U19 players over 5m (p < 0.05, ES 0.36-0.58) while elite were faster over 20m compared to all groups (p < 0.01, ES 0.45-0.72). Elite achieved a greater distance (1350.8m; p < 0.05, ES 0.32-0.50) in the Yo-YoIRT1 compared to the sub-elite, regional, U19 and U17. VJ height significantly increased from the 2014 (51.6 ± 4.8cm) to the 2017 season (59.6 ± 6.3cm) for the elite players (p < 0.01, ES 1.18). Yo-YoIRT1 test scores increased significantly between the pre-season and in-season phases (p < 0.05, ES 0.17).

The Chronic Effect of Interval Training on Energy Intake: A Systematic Review and Meta-Analysis.

Single bouts of acute exercise do not appear to increase subsequent energy intake (EI), even when energy deficit is large. However, studies have shown a compensatory effect on EI following chronic exercise, and it remains unclear whether this is affected by exercise intensity. We investigated the chronic effect of high-intensity interval training (HIIT) and sprint interval training (SIT) on EI when compared with moderate-intensity continuous training (MICT) or no exercise (CON). Databases were searched until 13 March 2017 for studies measuring EI in response to chronic exercise (≥4 weeks of duration) of a high-intensity interval nature. Meta-analysis was conducted for between-group comparisons on EI (kilojoules) and bodyweight (kg). Results showed large heterogeneity, and therefore, metaregression analyses were conducted. There were no significant differences in EI between HIIT/SIT versus MICT (P=0.282), HIIT/SIT versus CON (P=0.398), or MICT versus CON (P=0.329). Although bodyweight was significantly reduced after HIIT/SIT versus CON but not HIIT/SIT versus MICT (in studies measuring EI), this was not clinically meaningful (<2% mean difference). In conclusion, there is no compensatory increase in EI following a period of HIIT/SIT compared to MICT or no exercise. However, this review highlights important methodological considerations for future studies.

Combined Carbohydrate and Protein Ingestion During Australian Rules Football Matches and Training Sessions Does Not Reduce Fatigue or Accelerate Recovery Throughout a Weeklong Junior Tournament.

Lee, NA, Fell, JW, Pitchford, NW, Hall, AH, Leveritt, MD, and Kitic, CM. Combined carbohydrate and protein ingestion during Australian rules football matches and training sessions does not reduce fatigue or accelerate recovery throughout a weeklong junior tournament. J Strength Cond Res 32(2): 344-355, 2018-Australian rules football (ARF) is a physically demanding sport that can induce high levels of fatigue. Fatigue may be intensified during periods where multiple matches are played with limited recovery time. Combined carbohydrate and protein (CHO + PRO) intake during physical activity may provide performance and recovery benefits. The aim of this study was to investigate whether CHO + PRO ingestion during ARF matches and training sessions throughout a tournament would enhance performance or recovery in comparison with CHO-only ingestion. Australian rules football players (n = 21) competing in a 7-day national tournament participated in this randomized and double-blinded study. Beverages containing either CHO (n = 10) or CHO + PRO (n = 11) were provided during matches (day 1, day 4, and day 7) and training sessions (day 2 and day 3). Countermovement jumps (CMJs), ratings of muscle soreness, and autonomic function were assessed throughout the tournament. Gastrointestinal tract (GI) discomfort was measured after matches. Countermovement jump peak velocity increased in the CHO + PRO group (p = 0.01) but not in the CHO group. There were no differences in the other CMJ variables. In both groups, muscle soreness increased from days 0 and 1 to day 2 (p ≤ 0.05) but did not remain elevated. R-R intervals (time elapsed between successive peaks in QRS complexes) increased in both groups from day 1 to day 7 (mean difference = 59.85 ms, p < 0.01). Postmatch GI discomfort was not different (p > 0.05) between groups. When daily dietary protein is adequate (>1.8 g·kg·d), the ingestion of CHO + PRO during matches and training sessions throughout a tournament does not reduce muscle soreness nor have clear benefits for neuromuscular recovery or modulate autonomic function in junior ARF athletes, compared with that of CHO alone.

The Influence of Drinking Fluid on Endurance Cycling Performance: A Meta-Analysis.

BACKGROUND: Fluid replacement during cycling exercise evolves on a spectrum from simply drinking to thirst to planned structured intake, with both being appropriate recommendations. However, with mixed findings suggesting fluid intake may or may not improve endurance cycling performance (ECP) in a diverse range of trained individuals, there is a clear need for summarised evidence regarding the effect of fluid consumption on ECP. OBJECTIVES: (1) Determine the magnitude of the effect of drinking fluid on performance during cycling exercise tasks of various durations, compared with no drinking; (2) examine the relationship between rates of fluid intake and ECP; and (3) establish fluid intake recommendations based on the observations between rates of fluid intake and ECP. STUDY DESIGN: Meta-analysis. METHODS: Studies were located via database searches and cross-referencing. Performance outcomes were converted to a similar metric to represent percentage change in power output. Fixed- and random-effects weighted mean effect summaries and meta-regression analyses were used to identify the impact of drinking fluid on ECP. RESULTS: A limited number of research manuscripts (n = 9) met the inclusion criteria, producing 15 effect estimates. Meta-regression analyses demonstrated that the impact of drinking on ECP under 20-33 °C ambient temperatures was duration-dependent. Fluid consumption of, on average, 0.29 mL/kg body mass/min impaired 1 h high-intensity (80% peak oxygen uptake [[Formula: see text]o2peak]) ECP by -2.5 ± 0.8% (95% confidence interval [CI] -4.1 to -0.9%) compared with no fluid ingestion. In contrast, during >1 to ≤2 h and >2 h moderate-intensity (60-70% [Formula: see text]o2peak) cycling exercise, ECP improved by 2.1 ± 1.5% (95% CI 1.2-2.9%) and 3.2 ± 1.2% (95% CI 0.8-5.6%), respectively, with fluid ingestion compared with no fluid intake. The associated performance benefits were observed when the rates of fluid intake were in the range of 0.15-0.20 mL/kg body mass/min for >1 to ≤2 h cycling exercise and ad libitum or 0.14-0.27 mL/kg body mass/min for cycling exercise >2 h. CONCLUSIONS: A rate of fluid consumption of between 0.15 and 0.34 mL/kg body mass/min during high-intensity 1 h cycling exercise is associated with reductions in ECP. When cycling at moderate intensity for >1 to ≤2 h, cyclists should expect a gain in performance of at least 2% if fluid is consumed at a rate of 0.15-0.20 mL/kg body mass/min. For cycling exercise >2 h conducted at moderate intensity, consuming fluid ad libitum or at a rate of 0.14-0.27 mL/kg body mass/min should improve performance by at least 3%. Until further research is conducted, these recommendations should be used as a guide to inform hydration practices.

Nutrition therapy with high intensity interval training to improve prostate cancer-related fatigue in men on androgen deprivation therapy: a study protocol.

BACKGROUND: Cancer-related fatigue is one of the most prevalent, prolonged and distressing side effects of prostate cancer treatment with androgen deprivation therapy. Preliminary evidence suggests natural therapies such as nutrition therapy and structured exercise prescription can reduce symptoms of cancer-related fatigue. Men appear to change their habitual dietary patterns after prostate cancer diagnosis, yet prostate-specific dietary guidelines provide limited support for managing adverse side effects of treatment. The exercise literature has shown high intensity interval training can improve various aspects of health that are typically impaired with androgen deprivation therapy; however exercise at this intensity is yet to be conducted in men with prostate cancer. The purpose of this study is to examine the effects of nutrition therapy beyond the current healthy eating guidelines with high intensity interval training for managing cancer-related fatigue in men with prostate cancer treated with androgen deprivation therapy. METHODS/DESIGN: This is a two-arm randomized control trial of 116 men with prostate cancer and survivors treated with androgen deprivation therapy. Participants will be randomized to either the intervention group i.e. nutrition therapy and high intensity interval training, or usual care. The intervention group will receive 20 weeks of individualized nutrition therapy from an Accredited Practising Dietitian, and high intensity interval training (from weeks 12-20 of the intervention) from an Accredited Exercise Physiologist. The usual care group will maintain their standard treatment regimen over the 20 weeks. Both groups will undertake primary and secondary outcome testing at baseline, week 8, 12, and 20; testing includes questionnaires of fatigue and quality of life, objective measures of body composition, muscular strength, cardiorespiratory fitness, biomarkers for disease progression, as well as dietary analysis. The primary outcomes for this trial are measures of fatigue and quality of life. DISCUSSION: This study is the first of its kind to determine the efficacy of nutrition therapy above the healthy eating guidelines and high intensity interval training for alleviating prostate-cancer related fatigue. If successful, nutrition therapy and high intensity interval training may be proposed as an effective therapy for managing cancer-related fatigue and improving quality of life in men during and after prostate cancer treatment. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12615000512527 . Trial registered on the 22/5/2015.

Study protocol for the FITR Heart Study: Feasibility, safety, adherence, and efficacy of high intensity interval training in a hospital-initiated rehabilitation program for coronary heart disease.

BACKGROUND: For decades, moderate intensity continuous training (MICT) has been the cornerstone of exercise prescription for cardiac rehabilitation (CR). High intensity interval training (HIIT) is now recognized in CR exercise guidelines as an appropriate and efficient modality for improving cardiorespiratory fitness, a strong predictor of mortality. However, the clinical application of HIIT in a real world CR setting, in terms of feasibility, safety, and long-term adherence, needs further investigation to address ongoing reservations. Furthermore, studies using objective measures of exercise intensity (such as heart rate; HR) have produced variable outcomes. Therefore we propose investigating the use of subjective measures (such as rating of perceived exertion (RPE)) for prescribing exercise intensity. METHODS: One hundred adults with coronary artery disease (CAD) attending a hospital-initiated CR program will be randomized to 1) HIIT: 4 × 4 min high intensity intervals at 15-18 RPE interspersed with 3-min active recovery periods or 2) MICT: usual care exercise including 40 min continuous exercise at a moderate intensity corresponding to 11-13 RPE. Primary outcome is change in exercise capacity (peak VO2) following 4 weeks of exercise training. Secondary outcome measures are: feasibility, safety, exercise adherence, body composition, vascular function, inflammatory markers, intrahepatic lipid, energy intake, and dietary behavior over 12-months; and visceral adipose tissue (VAT) following 12 weeks of exercise training. CONCLUSIONS: This study aims to address the ongoing concerns regarding the practicality and safety of HIIT in CR programs. We anticipate study findings will lead to the development of a standardized protocol to facilitate CR programs to incorporate HIIT as a standard exercise option for appropriate patients.

Prevalence, knowledge and attitudes relating to ß-alanine use among professional footballers.

OBJECTIVES: To investigate ß-alanine supplementation use and level of knowledge amongst professional footballers. DESIGN: Cross-sectional survey of Australian professional football players. METHODS: Questionnaires assessing ß-alanine supplementation behaviours, level of knowledge and sources of information were completed by professional rugby union (RU) (n=87), rugby league (RL) (n=180) and Australian Rules Football (ARF) (n=303) players. RESULTS: Approximately 61% of athletes reported ß-alanine use, however use by ARF football players (44%) was lower than that of RU (80%) and RL players (80%). The majority of respondents were not using ß-alanine in accordance with recommendations. Only 35% of the participants were able to correctly identify the potential benefits of ß-alanine supplementation. The main information sources that influenced players' decision to use ß-alanine were strength and conditioning coach (71%) and dietitian (52%). Forty-eight per cent of athletes never read labels prior to supplementing and only 11% completed their own research on ß-alanine. Compared to RL and ARF players, RU players had both a greater knowledge of ß-alanine supplementation and better supplementation practices. CONCLUSIONS: Despite over half the surveyed professional footballers using ß-alanine, the majority of athletes used ß-alanine in a manner inconsistent with recommendations. A better understanding of the environment and culture within professional football codes is required before supplement use becomes consistent with evidence based supplement recommendations.

Seasonal Changes in Soccer Players' Body Composition and Dietary Intake Practices.

Devlin, BL, Kingsley, M, Leveritt, MD, and Belski, R. Seasonal changes in soccer players' body composition and dietary intake practices. J Strength Cond Res 31(12): 3319-3326, 2017-The aims of this study were 2-fold: to determine seasonal changes in dietary intake and body composition in elite soccer players and to evaluate the influence of self-determined individual body composition goals on dietary intake and body composition. This longitudinal, observational study assessed body composition (total mass, fat-free soft tissue mass, and fat mass) using dual-energy x-ray absorptiometry and dietary intake (energy and macronutrients) via multiple-pass 24-hour recalls, at 4 time points over a competitive season in elite soccer players from one professional club in the Australian A-League competition. Self-reported body composition goals were also recorded. Eighteen elite male soccer players took part (25 ± 5 years, 180.5 ± 7.4 cm, 75.6 ± 6.5 kg). Majority (≥67%) reported the goal to maintain weight. Fat-free soft tissue mass increased from the start of preseason (55,278 ± 5,475 g) to the start of competitive season (56,784 ± 5,168 g; p < 0.001), and these gains were maintained until the end of the season. Fat mass decreased over the preseason period (10,072 ± 2,493 g to 8,712 ± 1,432 g; p < 0.001), but increased during the latter part of the competitive season. Dietary intake practices on training days were consistent over time and low compared with sport nutrition recommendations. The self-reported body composition goals did not strongly influence dietary intake practices or changes in body composition. This study has demonstrated that body composition changes over the course of a soccer season are subtle in elite soccer players despite relatively low self-reported intake of energy and carbohydrate.

The Effect of Dietary Nitrate Supplementation on Endurance Exercise Performance in Healthy Adults: A Systematic Review and Meta-Analysis.

BACKGROUND: Recent research into the use of dietary nitrates and their role in vascular function has led to it becoming progressively more popular amongst athletes attempting to enhance performance. OBJECTIVE: The objective of this review was to perform a systematic review and meta-analysis of the literature to evaluate the effect of dietary nitrate (NO3-) supplementation on endurance exercise performance. An additional aim was to determine whether the performance outcomes are affected by potential moderator variables. DATA SOURCES: Relevant databases such as Cochrane Library, Embase, PubMed, Ovid, Scopus and Web of Science were searched for the following search terms 'nitrates OR nitrate OR beetroot OR table beet OR garden beet OR red beet AND exercise AND performance' from inception to October 2015. STUDY SELECTION: Studies were included if a placebo versus dietary nitrate-only supplementation protocol was able to be compared, and if a quantifiable measure of exercise performance was ≥30 s (for a single bout of exercise or the combined total for multiple bouts). STUDY APPRAISAL AND SYNTHESIS: The literature search identified 1038 studies, with 47 (76 trials) meeting the inclusion criteria. Data from the 76 trials were extracted for inclusion in the meta-analysis. A fixed-effects meta-analysis was conducted for time trial (TT) (n = 28), time to exhaustion (TTE) (n = 22) and graded-exercise test (GXT) (n = 8) protocols. Univariate meta-regression was used to assess potential moderator variables (exercise type, dose duration, NO3- type, study quality, fitness level and percentage nitrite change). RESULTS: Pooled analysis identified a trivial but non-significant effect in favour of dietary NO3- supplementation [effect size (ES) = -0.10, 95 % Cl = -0.27 to 0.06, p > 0.05]. TTE trials had a small to moderate statistically significant effect in favour of dietary NO3- supplementation (ES = 0.33, 95 % Cl = 0.15-0.50, p < 0.01). GXT trials had a small but non-significant effect in favour of dietary NO3- supplementation in GXT performance measures (ES = 0.25, 95 % Cl = -0.06 to 0.56, p > 0.05). No significant heterogeneity was detected in the meta-analysis. No statistically significant effects were observed from the meta-regression analysis. CONCLUSION: Dietary NO3- supplementation is likely to elicit a positive outcome when testing endurance exercise capacity, whereas dietary NO3- supplementation is less likely to be effective for time-trial performance. Further work is needed to understand the optimal dosing strategies, which population is most likely to benefit, and under which conditions dietary nitrates are likely to be most effective for performance.