Carbohydrate–protein ingestion during recovery from prolonged exercise in man

Evidence supports that the ingestion of carbohydrate solutions in the post-exercise period can facilitate the restoration of exercise capacity both through providing the fluid necessary for rehydration and through stimulating carbohydrate storage. The accrual of this evidence has now established many components of the optimal carbohydrate feeding strategy during recovery and further progress has been sought through investigating the potential influence of other macronutrients. Specifically, combined ingestion of protein and carbohydrate may promote a more rapid re-synthesis of endogenous glycogen stores than when either nutrient is ingested in isolation. This possibility has led to speculation that ingestion of a mixed carbohydrate-protein solution (CHO–PRO) might restore the capacity for physical exercise more completely during a short-term recovery than when a matched quantity of carbohydrate alone is ingested. However, evidence in support of this hypothesis is not yet available and the present series of studies will therefore attempt to directly examine the effects of CHO–PRO ingestion on recovery of exercise capacity. [Continues.

An investigation into the relationship between plain water intake and glycated Hb (HbA1c) : a sex-stratified, cross-sectional analysis of the UK National Diet and Nutrition Survey (2008–2012)

The authors thank the study participants, the NDNS team, the UK Data Service and the dietary assessment assistants at MRC Human Nutrition Research who coded the food diaries. The NDNS was funded by the Food Standards Agency, the Department for Health in England and Public Health England. This work was supported by the Economic and Social Research Council (grant no.: ES/J50015X/1). The Economic and Social Research Council had no role in the design, analysis or writing of this article. All authors formulated the research questions and analysis plan. H. A. C., L. J. analysed the data. H. A. C. drafted the article. J. A. B., L. J. critically reviewed the article. All authors have approved the final version of the manuscript. All authors have received funding from the European Hydration Institute. J. A. B. has received funding from GlaxoSmithKline and PepsiCo.Peer reviewedPublisher PD

Is breakfast the most important meal of the day?

The Bath Breakfast Project is a series of randomised controlled trials exploring the effects of extended morning fasting on energy balance and health. These trials were categorically not designed to answer whether or not breakfast is the most important meal of the day. However, this review will philosophise about the meaning of that question and about what questions we should be asking to better understand the effects of breakfast, before summarising how individual components of energy balance and health respond to breakfast v. fasting in lean and obese adults. Current evidence does not support a clear effect of regularly consuming or skipping breakfast on body mass/composition, metabolic rate or diet-induced thermogenesis. Findings regarding energy intake are variable, although the balance of evidence indicates some degree of compensatory feeding later in the day such that overall energy intake is either unaffected or slightly lower when breakfast is omitted from the diet. However, even if net energy intake is reduced, extended morning fasting may not result in expected weight loss due to compensatory adjustments in physical activity thermogenesis. Specifically, we report that both lean and obese adults expended less energy during the morning when remaining in the fasted state than when consuming a prescribed breakfast. Further research is required to examine whether particular health markers may be responsive to breakfast-induced responses of individual components of energy balance irrespective of their net effect on energy balance and therefore body mass.</p

Phosphate Loading does not improve 30-km cycling time-trial performance in trained cyclists:phosphate and exercise performance

Phosphate is integral to numerous metabolic processes, several of which strongly predict exercise performance (i.e., cardiac function, oxygen transport, and oxidative metabolism). Evidence regarding phosphate loading is limited and equivocal, at least partly because studies have examined sodium phosphate supplements of varied molar mass (e.g., mono/di/tribasic, dodecahydrate), thus delivering highly variable absolute quantities of phosphate. Within a randomized cross-over design and in a singleblind manner, 16 well-trained cyclists (age 38 ± 16 years, mass 74.3 ± 10.8 kg, training 340 ± 171 min/week; mean ± SD) ingested either 3.5 g/day of dibasic sodium phosphate (Na2HPO4: 24.7 mmol/day phosphate; 49.4 mmol/day sodium) or a sodium chloride placebo (NaCl: 49.4 mmol/day sodium and chloride) for 4 days prior to each of two 30-km time trials, separated by a washout interval of 14 days. There was no evidence of any ergogenic benefit associated with phosphate loading. Time to complete the 30-km time trial did not differ following ingestion of sodium phosphate and sodium chloride (3,059 ± 531 s vs. 2,995 ± 467 s). Accordingly, neither absolute mean power output (221 ± 48 W vs. 226 ± 48 W) nor relative mean power output (3.02 ± 0.78 W/kg vs. 3.08 ± 0.71 W/kg) differed meaningfully between the respective intervention and placebo conditions. Measures of cardiovascular strain and ratings of perceived exertion were very closely matched between treatments (i.e., average heart rate 161 ± 11 beats per minute vs. 159 ± 12 beats per minute; Δ2 beats per minute; and ratings of perceived exertion 18 [14- 20] units vs. 17 [14-20] units). In conclusion, supplementing with relatively high absolute doses of phosphate (i.e., &gt;10 mmol daily for 4 days) exerted no ergogenic effects on trained cyclists completing 30-km time trials.</p

Taxonomic voucher specimens for study of bee communities in intensively managed Douglas-fir forests in the Oregon Coast Range

Understanding how pollinators respond to anthropogenic land use is key to conservation of biodiversity and ecosystem services, but few studies have addressed this topic in coniferous forests, particularly those managed intensively for wood production. This study reports on voucher material generated as part of Zitomer et al. (2023), that assessed changes in wild bee communities with time since harvest in 60 intensively managed Douglas-fir (Pseudotsuga menziesii) stands in the Oregon Coast Range across a gradient in stand age spanning a typical harvest rotation (0-37 years post-harvest). We additionally assessed relationships of bee diversity and community composition to relevant habitat features, including availability of floral resources and nest sites, understory vegetation characteristics, and composition of the surrounding landscape. Specimens were collected using a combination of passive sampling methods-blue vane traps and white, blue, and yellow bowl traps- and hand-netting and were identified to the lowest possible taxonomic level by A.R. Moldenke and L.R. Best. Four hundred and ten taxonomic voucher specimens were deposited into the Oregon State Arthropod Collection (Accession# OSAC_AC_2023_01_09-001-01) to serve as a reference for future research

Ketone monoester ingestion increases post-exercise serum erythropoietin concentrations in healthy men:Ketones and EPO

Intravenous ketone body infusion can increase erythropoietin (EPO) concentrations, but responses to ketone monoester ingestion postexercise are currently unknown. The purpose of this study was to assess the effect of ketone monoester ingestion on postexercise erythropoietin (EPO) concentrations. Nine healthy men completed two trials in a randomized, crossover design (1-wk washout). During trials, participants performed 1 h of cycling (initially alternating between 50% and 90% of maximal aerobic capacity for 2 min each interval, and then 50% and 80%, and 50% and 70% when the higher intensity was unsustainable). Participants ingested 0.8 g·kg-1 sucrose with 0.4 g·kg-1 protein immediately after exercise, and at 1, 2, and 3 h postexercise. During the control trial (CONTROL), no further nutrition was provided, whereas on the ketone monoester trial (KETONE), participants also ingested 0.29 g·kg-1 of the ketone monoester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate immediately postexercise and at 1 and 2 h postexercise. Blood was sampled immediately postexercise, every 15 min in the first hour and hourly thereafter for 4 h. Serum EPO concentrations increased to a greater extent in KETONE than in CONTROL (time × condition interaction: P = 0.046). Peak serum EPO concentrations were higher with KETONE (means ± SD: 9.0 ± 2.3 IU·L-1) compared with CONTROL (7.5 ± 1.5 IU·L-1, P &lt; 0.01). Serum β-hydroxybutyrate concentrations were also higher, and glucose concentrations lower, with KETONE versus CONTROL (both P &lt; 0.01). In conclusion, ketone monoester ingestion increases postexercise erythropoietin concentrations, revealing a new avenue for orally ingestible ketone monoesters to potentially alter hemoglobin mass.NEW &amp; NOTEWORTHY To our knowledge, this study was the first to assess the effects of ketone monoester ingestion on erythropoietin concentrations after exercise. We demonstrated that ingestion of a ketone monoester postexercise increased serum erythropoietin concentrations and reduced serum glucose concentrations in healthy men. These data reveal the possibility for ketone monoesters to alter hemoglobin mass.</p