Swifter, higher, stronger: What’s on the menu?

Burke, Louise M.; Hawley, John A.

doi:10.1126/science.aau2093

Cited by 90 publications

(100 citation statements)

References 95 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Physiological responses to exercise performed within moderate-(<LT), heavy-(>LT but <CS), and severe (>CS)intensity domains differ considerably (Poole et al, 2016) with implications for the predominant cause(s) of fatigue (Black et al, 2017). The goal of race nutrition is to address the factors that would otherwise cause fatigue or suboptimal outputs during and especially toward the end of an event (Burke & Hawley, 2018). Table 1 indicates that substrate availability for the muscle (glycogen and glucose) and brain (glucose) is a key issue for many distance events, along with the offset of sweat loss to preserve plasma volume and cardiac output.…”

mentioning

confidence: 99%

Contemporary Nutrition Strategies to Optimize Performance in Distance Runners and Race Walkers

Burke

Jeukendrup

Jones

et al. 2019

International Journal of Sport Nutrition and Exercise Metabolism

Self Cite

106

View full text Add to dashboard Cite

Distance events in Athletics include cross country, 10,000-m track race, half-marathon and marathon road races, and 20-and 50-km race walking events over different terrain and environmental conditions. Race times for elite performers span ∼26 min to >4 hr, with key factors for success being a high aerobic power, the ability to exercise at a large fraction of this power, and high running/walking economy. Nutrition-related contributors include body mass and anthropometry, capacity to use fuels, particularly carbohydrate (CHO) to produce adenosine triphosphate economically over the duration of the event, and maintenance of reasonable hydration status in the face of sweat losses induced by exercise intensity and the environment. Race nutrition strategies include CHO-rich eating in the hours per days prior to the event to store glycogen in amounts sufficient for event fuel needs, and in some cases, in-race consumption of CHO and fluid to offset event losses. Beneficial CHO intakes range from small amounts, including mouth rinsing, in the case of shorter events to high rates of intake (75-90 g/hr) in the longest races. A personalized and practiced race nutrition plan should balance the benefits of fluid and CHO consumed within practical opportunities, against the time, cost, and risk of gut discomfort. In hot environments, prerace hyperhydration or cooling strategies may provide a small but useful offset to the accrued thermal challenge and fluid deficit. Sports foods (drinks, gels, etc.) may assist in meeting training/race nutrition plans, with caffeine, and, perhaps nitrate being used as evidence-based performance supplements.

show abstract

mentioning

confidence: 99%

Contemporary Nutrition Strategies to Optimize Performance in Distance Runners and Race Walkers

Burke

Jeukendrup

Jones

et al. 2019

International Journal of Sport Nutrition and Exercise Metabolism

Self Cite

106

View full text Add to dashboard Cite

show abstract

“…At the molecular level, exercise with reduced CHO availability enhances expression and/or activity of proteins involved in oxidative metabolism of fatty acids (FAs) and mitochondrial biogenesis in skeletal muscle. 3,15,16 Evidence suggests that the molecular mechanism for this involves activation of AMP-activated protein kinase (AMPK) and the downstream transcription factor, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α). [17][18][19] While mitochondrial adaptations have been investigated extensively, intramuscular lipolysis has not received similar attention.…”

mentioning

confidence: 99%

Acute and sustained effects of a periodized carbohydrate intake using the sleep‐low model in endurance‐trained males

Riis

Møller

Dollerup

et al. 2019

Scandinavian Med Sci Sports

View full text Add to dashboard Cite

Repeated periodization of carbohydrate (CHO) intake using a diet‐exercise strategy called the sleep‐low model can potentially induce mitochondrial biogenesis and improve endurance performance in endurance‐trained individuals. However, more studies are needed to confirm the performance‐related effects and to investigate the sustained effects on maximal fat oxidation (MFO) rate and proteins involved in intramuscular lipid metabolism. Thirteen endurance‐trained males (age 23‐44 years; trueV˙O2‐max, 63.9 ± 4.6 mL·kg−1·min−1) were randomized into two groups: sleep‐low (LOW‐CHO) or high CHO availability (HIGH‐CHO) in three weekly training blocks over 4 weeks. The acute metabolic response was investigated during 60 minutes of exercise within the last 3 weeks of the intervention. Pre‐ and post‐intervention, 30‐minute time‐trial performance was investigated after a 90‐minute pre‐load, which as a novel approach included nine intense intervals (and estimation of MFO). Additionally, muscle biopsies (v. lateralis) were obtained to investigate expression of proteins involved in intramuscular lipid metabolism using Western blotting. During acute exercise, average fat oxidation rate was ~36% higher in LOW‐CHO compared to HIGH‐CHO (P = .03). This did not translate into sustained effects on MFO. Time‐trial performance increased equally in both groups (overall time effect: P = .005). We observed no effect on intramuscular proteins involved in lipolysis (ATGL, G0S2, CGI‐58, HSL) or fatty acid transport and β‐oxidation (CD‐36 and HAD, respectively). In conclusion, the sleep‐low model did not induce sustained effects on MFO, endurance performance, or proteins involved in intramuscular lipid metabolism when compared to HIGH‐CHO. Our study therefore questions the transferability of acute effects of the sleep‐low model to superior sustained adaptations.

show abstract

“…We also showed that net skeletal muscle glycogen utilization and acute skeletal muscle mRNA responses were largely unaffected by the same exercise performed before versus after breakfast. This is important, because muscle glycogen availability can alter muscle adaptations to training (27). Lower muscle glycogen concentrations are therefore unlikely to have driven the training responses we observed in the training study with the present method of nutrient-exercise timing.…”

Section: Discussionmentioning

confidence: 99%

“…Emerging data in lean, healthy men suggests that nutrient provision affects adaptive responses to exercise training (26, 27). However, feeding and fasting may exert different physiological responses in people who are overweight or obese compared to lean individuals, for example, extended morning fasting versus daily breakfast consumption upregulates the expression of genes involved in lipid turnover in adipose tissue in lean, but not in obese humans (28).…”

Section: Introductionmentioning

confidence: 99%

Lipid metabolism links nutrient-exercise timing to insulin sensitivity in men classified as overweight or obese

Edinburgh

Bradley

Abdullah

et al. 2019

Preprint

View full text Add to dashboard Cite

62Context: Pre-exercise nutrient availability alters acute metabolic responses to 63 exercise, which could modulate training responsiveness. We hypothesised that in 64 men with overweight/obesity, acute exercise before versus after nutrient ingestion 65 would increase whole-body and intramuscular lipid utilization, translating into greater 66 increases in oral glucose insulin sensitivity over 6-weeks of training. 67 Design and Participants:We showed in men with overweight/obesity (mean±SD 68 for BMI: 30.2±3.5 kg×m -2 for acute, crossover study, 30.9±4.5 kg×m -2 for randomized, 69 controlled, training study) a single exercise bout before versus after nutrient 70 provision increased lipid utilisation at the whole-body level, but also in both type I 71 (p<0.01) and type II muscle fibres (p=0.02). We then used a 6-week training 72 intervention to show sustained, 2-fold increases in lipid utilisation with exercise 73 before versus after nutrient provision (p<0.01). 74Main Outcome Measures: Postprandial glycemia was not differentially affected by 75 exercise training before vs after nutrient provision (p>0.05), yet plasma was reduced 76 with exercise training before, but not after nutrient provision (p=0.03), resulting in 77 increased oral glucose insulin sensitivity when training was performed before versus 78 after nutrient provision (25±38 vs -21±32 mL×min -1 ×m -2 ; p=0.01) and this was 79 associated with increased lipid utilisation during exercise (r=0.50, p=0.02). Regular 80 exercise prior to nutrient provision augmented remodelling of skeletal muscle 81 phospholipids and protein content of the glucose transport protein GLUT4 (p<0.05). 82 Conclusions: Experiments investigating exercise training and metabolic health 83 should consider nutrient-exercise timing, and exercise performed before versus after 84 nutrient intake (i.e., in the fasted state) may exert beneficial effects on lipid utilisation 85 and reduce postprandial insulinemia.86 Page 5 of 57 Précis 87 Exercise in the fasted-versus fed-state increased intramuscular and whole-body 88 lipid use, translating into increased muscle adaptation and insulin sensitivity when 89 regularly performed over 6 weeks. 91 Postprandial hyperinsulinemia and associated peripheral insulin resistance are key 92 drivers of metabolic diseases, such as type 2 diabetes (T2D) and cardiovascular 93 disease (1-3). Obesity and a sedentary lifestyle are independently associated with 94 changes in skeletal muscle that can reduce insulin sensitivity (4,5) and increase 95 hyperinsulinemia, contributing to elevated cardiovascular disease risk (2). Therefore, 96 increasing insulin sensitivity and reducing postprandial insulinemia are important 97 targets for interventions to reduce the risk of metabolic disease. 98 99 Regular exercise training represents a potent strategy to increase peripheral insulin 100 sensitivity and to reduce postprandial insulinemia (6). The beneficial effects of 101 exercise on oral glucose tolerance and insulin sensitivity can be attributed to both an 102 'ac...

show abstract

Swifter, higher, stronger: What’s on the menu?

Cited by 90 publications

References 95 publications

Contemporary Nutrition Strategies to Optimize Performance in Distance Runners and Race Walkers

Contemporary Nutrition Strategies to Optimize Performance in Distance Runners and Race Walkers

Acute and sustained effects of a periodized carbohydrate intake using the sleep‐low model in endurance‐trained males

Lipid metabolism links nutrient-exercise timing to insulin sensitivity in men classified as overweight or obese

Contact Info

Product

Resources

About