BackgroundWhile it is well established that dietary nitrate reduces the metabolic cost of exercise, recent evidence suggests this effect is maintained 24 h following the final nitrate dose when plasma nitrite levels have returned to baseline. In addition, acute dietary nitrate was recently reported to enhance peak power production. Our purpose was to examine whether chronic dietary nitrate supplementation enhanced peak power 24 h following the final dose and if this impacted performance in a heavily power-dependent sport.MethodsIn a double-blind, randomized, crossover design, maximal aerobic capacity, body composition, strength, maximal power (30 s Wingate), endurance (2 km rowing time trial), and CrossFit performance (Grace protocol) were assessed before and after six days of supplementation with nitrate (NO) (8 mmol·potassium nitrate·d−1) or a non-caloric placebo (PL). A 10-day washout period divided treatment conditions. Paired t-tests were utilized to assess changes over time and to compare changes between treatments.ResultsPeak Wingate power increased significantly over time with NO (889.17 ± 179.69 W to 948.08 ± 186.80 W; p = 0.01) but not PL (898.08 ± 183.24 W to 905.00 ± 157.23 W; p = 0.75). However, CrossFit performance was unchanged, and there were no changes in any other performance parameters.ConclusionConsuming dietary nitrate in the potassium nitrate salt form improved peak power during a Wingate test, but did not improve elements of strength or endurance in male CrossFit athletes.

Some of the universal characteristics of pre-agricultural hominin diets are strikingly different from the modern human diet. Hominin dietary choices were limited to wild plant and wild animal foods, while the modern diet includes more than 70 % of energy consumed from refined sugars, refined vegetable oils, and highly processed cereals and dairy products. The modern diet, with higher intake of fat has also resulted in a higher ratio of omega-6 (n-6) to omega-3 (n-3) polyunsaturated fatty acids (PUFA), contributing to low-grade chronic inflammation (LGCI) and thus promoting the development of many chronic diseases, including obesity and osteoporosis. In this review, we describe the changes in modern diet, focusing on the kind and amount of consumed fat; explain the shortcomings of the modern diet with regard to inflammatory processes; and delineate the reciprocity between adiposity and inflammatory processes, with inflammation being a common link between obesity and osteoporosis. We present the evidence that overconsumption of n-6 PUFA coupled with under-consumption of n-3 PUFA results in LGCI and, along with the increased presence of reactive oxygen species, leads to a shift in mesenchymal stem cells (precursors for both osteoblasts and adipocytes) lineage commitment toward increased adipogenesis and suppressed osteoblastogenesis. In turn, high n-6 to n-3 PUFA ratios in the modern diet, coupled with increased synthesis of pro-inflammatory cytokines due to adiposity, propagate obesity and osteoporosis by increasing or maintaining LGCI.

Postmenopausal women have increased wave reflection (augmentation pressure (AP) and index (AIx)) and reduced muscle function that predispose them to cardiac diseases and disability. Our aim was to examine the combined and independent effects of whole-body vibration training (WBVT) and l-citrulline supplementation on aortic hemodynamics and plasma nitric oxide metabolites (NOx) in postmenopausal women. Forty-one obese postmenopausal women were randomized to 3 groups: l-citrulline, WBVT+l-citrulline and WBVT+Placebo for 8 weeks. Brachial and aortic systolic blood pressure, diastolic blood pressure, AP, AIx, AIx adjusted to 75 beats/min (AIx@75), and NOx were measured before and after 8 weeks. All groups similarly decreased (P < 0.05) brachial and aortic pressures as well as AP, and similarly increased (P < 0.05) NOx levels. AIx and AIx@75 decreased (P < 0.01) in the WBVT+l-citrulline and WBVT+Placebo groups, but not in the l-citrulline group. The improvement in AIx@75 (-10.5% ± 8.8%, P < 0.05) in the WBVT+l-citrulline group was significant compared with the l-citrulline group. l-Citrulline supplementation and WBVT alone and combined decreased blood pressures. The combined intervention reduced AIx@75. This study supports the effectiveness of WBVT+l-citrulline as a potential intervention for prevention of hypertension-related cardiac diseases in obese postmenopausal women.

The timing of morning endurance competition may limit proper pre-race fueling and resulting performance. A nighttime, pre-sleep nutritional strategy could be an alternative method to target the metabolic and hydrating needs of the early morning athlete without compromising sleep or gastrointestinal comfort during exercise. Therefore, the purpose of this investigation was to examine the acute effects of pre-sleep chocolate milk (CM) ingestion on next-morning running performance, metabolism, and hydration status. Twelve competitive female runners and triathletes (age, 30 ± 7 years; peak oxygen consumption, 53 ± 4 mL·kg(-1)·min(-1)) randomly ingested either pre-sleep CM or non-nutritive placebo (PL) ∼30 min before sleep and 7-9 h before a morning exercise trial. Resting metabolic rate (RMR) was assessed prior to exercise. The exercise trial included a warm-up, three 5-min incremental workloads at 55%, 65%, and 75% peak oxygen consumption, and a 10-km treadmill time trial (TT). Physiological responses were assessed prior, during (incremental and TT), and postexercise. Paired t tests and magnitude-based inferences were used to determine treatment differences. TT performances were not different ("most likely trivial" improvement with CM) between conditions (PL: 52.8 ± 8.4 min vs CM: 52.8 ± 8.0 min). RMR was "likely" increased (4.8%) and total carbohydrate oxidation (g·min(-1)) during exercise was "possibly" or likely increased (18.8%, 10.1%, 9.1% for stage 1-3, respectively) with CM versus PL. There were no consistent changes to hydration indices. In conclusion, pre-sleep CM may alter next-morning resting and exercise metabolism to favor carbohydrate oxidation, but effects did not translate to 10-km running performance improvements.

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