Medium chain triglycerides (MCTs) are ketogenic and might reduce adverse effects of keto-induction and improve time to ketosis and the tolerability of very low carbohydrate diets. This study investigates whether MCT supplementation improves time to nutritional ketosis (NK), mood, and symptoms of keto-induction. We compared changes in beta-hydroxybutyrate (BOHB), blood glucose, symptoms of keto-induction, and mood disturbance, in 28 healthy adults prescribed a ketogenic diet, randomised to receive either 30 ml of MCT, or sunflower oil as a control, three times per day, for 20 days. The primary outcome measured was the achievement of NK (≥0.5 mmol·L−1 BOHB). Participants also completed a daily Profile of Mood States and keto-induction symptom questionnaire. MCT resulted in higher BOHB at all time points and faster time to NK, a result that failed to reach significance. Symptoms of keto-induction resulted from both diets, with a greater magnitude in the control group, except for abdominal pain, which occurred with greater frequency and severity in the MCT-supplemented diet. There was a possibly beneficial effect on symptoms by MCT, but the effect on mood was unclear. Based on these results, MCTs increase BOHB compared with LCT and reduce symptoms of keto-induction. It is unclear whether MCTs significantly improve mood or time to NK. The trial was registered by the Australia New Zealand Clinical Trial Registry ACTRN12616001099415.

Actigraphy has become a common method of measuring sleep due to its non-invasive, cost-effective nature. An actigraph (Readiband™) that utilizes automatic scoring algorithms has been used in the research, but is yet to be evaluated for its inter-device reliability. A total of 77 nights of sleep data from 11 healthy adult participants was collected while participants were concomitantly wearing two Readiband™ actigraphs attached together (ACT1 and ACT2). Sleep indices including total sleep time (TST), sleep latency (SL), sleep efficiency (SE%), wake after sleep onset (WASO), total time in bed (TTB), wake episodes per night (WE), sleep onset variance (SOV) and wake variance (WV) were assessed between the two devices using mean differences, 95% levels of agreement, intraclass correlation coefficients (ICC), typical error of measurement (TEM) and coefficient of variation (CV%) analysis. There were no significant differences between devices for any of the measured sleep variables (p>0.05). TST, SE, SL, TTB, SOV and WV all resulted in very high ICC's (>0.90), with WASO and WE resulting in high ICC's between devices (0.85 and 0.80, respectively). Mean differences of −2.1 and 0.2 min for TST and SL were associated with a low TEM between devices (9.5 and 3.8 min, respectively). SE resulted in a 0.3% mean difference between devices. The Readiband™ is a reliable tool for researchers using multiple devices of this brand in sleep studies to assess basic measures of sleep quality and quantity in healthy adult populations.

We aimed to compare the effects of two different dosing durations of dietary nitrate (NO) supplementation on 1 and 4 km cycling time-trial performance in highly trained cyclists. In a double-blind crossover-design, nine highly trained cyclists ingested 140ml of NO -rich beetroot juice containing ~8.0mmol [NO], or placebo, for seven days. Participants completed a range of laboratory-based trials to quantify physiological and perceptual responses and cycling performance: time-trials on day 3 and 6 (4km) and on day 4 and 7 (1km) of the supplementation period. Relative to placebo, effects following 3- and 4-days of NO supplementation were unclear for 4 (-0.8; 95% CL, ± 2.8%, p = .54) and likely harmful for 1km (-1.9; ± 2.5% CL, p = .17) time-trial mean power. Effects following 6- and 7-days of NO supplementation resulted in unclear effects for 4 (0.1; ± 2.2% CL, p = .93) and 1km (-0.9; ± 2.6%CL, p = .51) time-trial mean power. Relative to placebo, effects for 40, 50, and 60% peak power output were unclear for economy at days 3 and 6 of NO supplementation (p > .05). Dietary NO supplementation appears to be detrimental to 1km time-trial performance in highly trained cyclists after 4-days. While, extending NO dosing to ≥ 6-days reduced the magnitude of harm in both distances, overall performance in short duration cycling time-trials did not improve relative to placebo.

Three days of [Formula: see text] supplementation resulted in small increases in rectal temperature during low- to moderate-intensity exercise, but this did not appear to influence 4-km cycling time-trial performance in hot climates.