scholarly journals Effect of meal frequency and timing on physical performance

1997 ◽  
Vol 77 (S1) ◽  
pp. S91-S103 ◽  
Author(s):  
John A. Hawley ◽  
Louise M. Burke
Keyword(s):  
Liver Glycogen ◽  
High Energy ◽  
Physically Active ◽  
Post Exercise ◽  
Practical Strategy ◽  
Increase Energy Intake ◽  
Prolonged Training ◽  
Special Challenge ◽  
Cyclical Process ◽  
Eating Occasions

Two areas of sports nutrition in which the periodicity of eating has been studied relate to: (1) the habitually high energy intakes of many athletes, and (2) the optimization of carbohydrate(CHO) availability to enhance performance. The present paper examines how the timing and frequency of food and fluid intake can assist the athlete and physically-active person to improve their exercise performance in these areas. Frequent eating occasions provide a practical strategy allowing athletes to increase energy intake while concomitantly reducing the gastric discomfort of infrequent large meals. The optimization of CHO stores is a special challenge for athletes undertaking prolonged training or competition sessions. This is a cyclical process with post-exercise CHO ingestion promoting muscle and liver glycogen re-synthesis; pre-exercise feedings being practised to optimize substrate availability and feedings during exercise providing a readily-available source of exogenous fuel as endogenous stores become depleted. The timing and frequency of CHO intake at these various stages are crucial determinants for optimizing fuel availability to enhance exercise capacity.

scholarly journals Post-exercise hypotension of normotensive young men through track running sessions

2015 ◽  
Vol 21 (3) ◽  
pp. 192-195 ◽  
Author(s):  
Emerson Pardono ◽  
Manuella de Oliveira Fernandes ◽  
Luan Morais Azevêdo ◽  
Jeeser Alves de Almeida ◽  
Marcio Rabelo Mota ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Young Men ◽  
Daily Basis ◽  
Physically Active ◽  
Post Exercise ◽  
Laboratory Exercise ◽  
Practical Applications ◽  
Pharmacological Mechanism ◽  
Minute Post ◽  
Post Exercise Hypotension

INTRODUCTION: After a single session of physical exercise the blood pressure is reduced (post-exercise hypotension, PHE) and it has been considered as a non-pharmacological mechanism to control the blood pressure. When the exercise is performed since youth it can prevent or avoid hypertension. However, it is important to consider studies with clear practical applications to optimize its reproducibility on a daily basis. OBJECTIVE: Analyze the PEH of normotensive and physically active young men after two track running sessions (maximum and submaximal). METHODS: Participated in this study 62 physically active young men (23.3 ± 4.2 years old; 75.5 ± 9.8 kg; 177.7 ± 5.5 cm; 12.0 ± 4.6% body fatF; 52.4 ± 4.0 mL.kg-1.min-1oxygen uptake), which performed a maximum laboratory exercise test for determination of maximal oxygen uptake (VO2max - aerobic power) and subsequently three randomly running sessions (maximum - T1600; submaximal - T20; control - CON), with 48h interval between themselves. Blood pressure (BP) was measured each 15min during a 60 min period after sessions. RESULTS: Both the maximum and the submaximal exercise lead to PEH. The post-exercise values of systolic blood pressure and diastolic blood pressure differed from resting value in session T20 (p<0.05). The same pattern occurred after T1600 (p<0.05), evidenced from 30th minute post-exercise. The CON did not result in PEH. The magnitude of decay for the mean BP at the 45th after maximum exercise was higher than the other sessions (p<0.05). CONCLUSION: We concluded that both maximum and submaximal exercises, performed on a track running condition, caused PEH in young normotensive and physically active men.

scholarly journals Effect of Simulated Matches on Post-Exercise Biochemical Parameters in Women’s Indoor and Beach Handball

2020 ◽  
Vol 17 (14) ◽  
pp. 5046
Author(s):  
Joanna Kamińska ◽  
Tomasz Podgórski ◽  
Jakub Kryściak ◽  
Maciej Pawlak
Keyword(s):  
Blood Parameters ◽  
Ion Concentration ◽  
Electrolyte Balance ◽  
Acid Base Balance ◽  
Acid Base ◽  
Urine Ph ◽  
Physically Active ◽  
Post Exercise ◽  
Before And After ◽  
Base Balance

This study assesses the status of hydration and the acid-base balance in female handball players in the Polish Second League before and after simulated matches in both indoor (hall) and beach (outdoor) conditions. The values of biochemical indicators useful for describing water-electrolyte management, such as osmolality, hematocrit, aldosterone, sodium, potassium, calcium, chloride and magnesium, were determined in the players’ fingertip capillary blood. Furthermore, the blood parameters of the acid-base balance were analysed, including pH, standard base excess, lactate and bicarbonate ion concentration. Additionally, the pH and specific gravity of the players’ urine were determined. The level of significance was set at p < 0.05. It was found that both indoor and beach simulated matches caused post-exercise changes in the biochemical profiles of the players’ blood and urine in terms of water-electrolyte and acid-base balance. Interestingly, the location of a simulated match (indoors vs. beach) had a statistically significant effect on only two of the parameters measured post-exercise: concentration of calcium ions (lower indoors) and urine pH (lower on the beach). A single simulated game, regardless of its location, directly affected the acid-base balance and, to a smaller extent, the water-electrolyte balance, depending mostly on the time spent physically active during the match.

scholarly journals Pre-Bed Casein Protein Supplementation Does Not Enhance Acute Functional Recovery in Physically Active Males and Females When Exercise is Performed in the Morning

Sports ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 5 ◽  
Author(s):  
Eva Apweiler ◽  
David Wallace ◽  
Sarah Stansfield ◽  
Dean Allerton ◽  
Meghan Brown ◽  
...  
Keyword(s):  
Muscle Soreness ◽  
Pressure Pain Threshold ◽  
Protein Supplementation ◽  
Group Differences ◽  
Physically Active ◽  
Post Exercise ◽  
Brief Assessment ◽  
Drop Jumps ◽  
Casein Protein ◽  
Males And Females

This study examined whether consuming casein protein (CP) pre-sleep could accelerate acute recovery following muscle-damaging exercise. Thirty-nine active males and females performed 100 drop jumps in the morning, consumed their habitual diet during the day, and then within 30 min pre-bed consumed either ~40 g of CP (n = 19) or ~40 g of a carbohydrate-only control (CON) (n = 20). Maximal isometric voluntary contractions (MIVC), countermovement jumps (CMJ), pressure-pain threshold (PPT), subjective muscle soreness and the brief assessment of mood adapted (BAM+) were measured pre, 24 and 48 h following the drop jumps. MIVC decreased in CP and CON post-exercise, peaking at 24 h post (CP: −8.5 ± 3.5 vs. CON: −13.0 ± 2.9%, respectively); however, no between-group differences were observed (p = 0.486; ηp2 =0.02). There were also no group differences in the recovery of CMJ height, PPT and BAM+ (p > 0.05). Subjective muscle soreness increased post-exercise, but no group differences were present at 24 h (CP: 92 ± 31 mm vs. CON: 90 ± 46 mm) or 48 h (CP: 90 ± 44 mm vs. CON: 80 ± 58 mm) (p > 0.05). These data suggest that pre-bed supplementation with ~40 g of CP is no more beneficial than CON for accelerating the recovery following muscle-damaging exercise.

The Effect Of Galactose And Fructose Containing Beverages On Liver Glycogen Synthesis Post-exercise

2009 ◽  
Vol 41 ◽  
pp. 89
Author(s):  
Jacques Décombaz ◽  
Roy L. Jentjens ◽  
Eva Scheurer ◽  
Michael Ith ◽  
Asker E. Jeukendrup ◽  
...  
Keyword(s):  
Glycogen Synthesis ◽  
Liver Glycogen ◽  
Post Exercise

scholarly journals Consistency in compensatory eating responses following acute exercise in inactive, overweight and obese women

2015 ◽  
Vol 113 (7) ◽  
pp. 1170-1177 ◽  
Author(s):  
Jessica L. Unick ◽  
Kevin C. O'Leary ◽  
Leah Dorfman ◽  
J. Graham Thomas ◽  
Kelley Strohacker ◽  
...  
Keyword(s):  
Acute Exercise ◽  
Intraclass Correlation ◽  
Exercise Bout ◽  
Moderate Intensity ◽  
Exercise Session ◽  
Obese Women ◽  
Post Exercise ◽  
Overweight Women ◽  
Increase Energy Intake ◽  
The Difference

It is often assumed that some individuals reliably increase energy intake (EI) post-exercise (‘compensators’) and some do not (‘non-compensators’), leading researchers to examine the characteristics that distinguish these two groups. However, it is unclear whether EI post-exercise is stable over time. The present study examined whether compensatory eating responses to a single exercise bout are consistent within individuals across three pairs of trials. Physically inactive, overweight/obese women (n28, BMI 30·3 (sd2·9) kg/m2) participated in three pairs of testing sessions, with each pair consisting of an exercise (30 min of moderate-intensity walking) and resting testing day. EI was measured using a buffet meal 1 h post-exercise/rest. For each pair, the difference in EI (EIdiff= EIex− EIrest) was calculated, where EIexis the EI of the exercise session and EIrestis the EI of the resting session, and women were classified as a ‘compensator’ (EIex>EIrest) or ‘non-compensator’ (EIex≤ EIrest). The average EI on exercise days (3328·0 (sd1686·2) kJ) was similar to those on resting days (3269·4 (sd1582·4) kJ) (P= 0·67). Although EI was reliable within individuals across the three resting days (intraclass correlation coefficient (ICC) 0·75, 95 % CI 0·60, 0·87;P< 0·001) and three exercise days (ICC 0·83, 95 % CI 0·70, 0·91;P< 0·001), the ICC for EIdiffacross the three pairs of trials was low (ICC 0·20, 95 % CI − 0·02, 0·45;P= 0·04), suggesting that compensatory eating post-exercise is not a stable construct. Moreover, the classification of ‘compensators’/‘non-compensators’ was not reliable (κ =− 0·048;P= 0·66). The results were unaltered when ‘relative’ EI was used, which considers the energy expenditure of the exercise/resting sessions. Acute compensatory EI following an exercise bout is not reliable in overweight women. Seeking to understand what distinguishes ‘compensators’ from ‘non-compensators’ based on a single eating episode post-exercise is not justified.

Smaller muscle ATP reduction in women than in men by repeated bouts of sprint exercise

2002 ◽  
Vol 93 (3) ◽  
pp. 1075-1083 ◽  
Author(s):  
Mona Esbjörnsson-Liljedahl ◽  
Kristina Bodin ◽  
Eva Jansson
Keyword(s):  
Muscle Fibers ◽  
Plasma Catecholamines ◽  
High Energy ◽  
Type I ◽  
High Energy Phosphates ◽  
Physically Active ◽  
Glycogen Accumulation ◽  
Repeated Sprints ◽  
Sprint Exercise ◽  
Freeze Dried

It was hypothesized that the reduction of high-energy phosphates in muscle after repeated sprints is smaller in women than in men. Fifteen healthy and physically active women and men with an average age of 25 yr (range of 19–42 yr) performed three 30-s cycle sprints (Wingate test) with 20 min of rest between sprints. Repeated blood and muscle samples were obtained. Freeze-dried pooled muscle fibers of types I and II were analyzed for high-energy phosphates and their breakdown products and for glycogen. Accumulation of plasma ATP breakdown products, plasma catecholamines, and blood lactate, as well as glycogen reduction in type I fibers, was all lower in women than in men during sprint exercise. Repeated sprints induced smaller reduction of ATP and smaller accumulation of IMP and inosine in women than in men in type II muscle fibers, with no gender differences in changes of ATP and its breakdown products during the bouts of exercise themselves. This indicates that the smaller ATP reduction in women than in men during repeated sprints was created during recovery periods between the sprint exercises and that women possess a faster recovery of ATP via reamination of IMP during these recovery periods.

scholarly journals T-cell responses to acute cardiorespiratory or resistance exercise in cohorts of physically active or physically inactive older adults: A randomized complete crossover

2021 ◽  
Author(s):  
Rachel M. Graff ◽  
Kristofer Jennings ◽  
Emily C. LaVoy ◽  
Victoria E. Warren ◽  
Brad W. Macdonald ◽  
...  
Keyword(s):  
Older Adults ◽  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Th17 Cells ◽  
T Cell Response ◽  
Moderate Intensity ◽  
Physically Active ◽  
Post Exercise ◽  
Age Related

AbstractAging is associated with many chronic diseases that are maintained and perpetuated by immune dysregulation and chronic systemic inflammation. T-cells often undergo age-related changes, including an accumulation of memory cells, which places individuals at increased risk for novel infections and may predispose them to increased inflammation. Regular exercise training has been suggested to offset age-related changes in T-cells, but the majority of literature is derived from cardiorespiratory exercise (CRE) studies. Much less is understood about the T-cell response to resistance exercise (RE). The purpose of this study was to examine the effects of acute CRE and acute RE on the T-cell response among a cohort of physically active older adults (PA) compared to a cohort of physically inactive older adults (PI).METHODSTwenty-four healthy older adults (PA n=12; PI n=12; mean ± SD; age (yrs) PA 62 ± 5, PI 64 ± 5; height (cm) PA 170.9 ± 6.9, PI 162.9 ± 8.0; weight (kg) PA 69.3 ± 10.2, PI 68.2 ± 12.8; BMI (kg/m2) PA 23.9 ± 3.0, PI 25.6 ± 3.5) completed one bout of CRE and one bout of RE in a randomized order, both at a moderate intensity, and separated by at least 7 days. Blood samples drawn pre-exercise, post-exercise, and 1h post-exercise (recovery) were analyzed for CD4+ and CD8+ T-cells and their differentiation status using surface markers CD45RA, CD62L, and CD57, as well as for Th17 cells (CD4+ CD161+ CD196+) using flow cytometry.RESULTSPI had higher numbers of circulating CD57+ EMRA CD4+ T-cells (PA, mean ± SE, 1 ± 2 cells/uL; PI, 6 ± 2 cells/uL; p=0.01; z=2.32) than PA at pre-exercise. Both CRE and RE elicited a significant mobilization of highly-differentiated (CD45RA+ CD62L-; CD57+ CD45RA+ CD62L-) CD8+ T-cells into the circulation post-exercise in both PA and PI groups. Furthermore, CRE resulted in a decrease in the number of circulating Th17 cells post-exercise, while RE increased Th17 cell mobilization compared to the CRE response.CONCLUSIONTaken together, T-cells in PA and PI respond similarly to acute CRE and support previously reported data showing a significant mobilization of highly differentiated T-cells. The present study confirms that moderate intensity RE also elicits this response, but highlights potential differences between CRE and RE on the immune responses of T-cells, particularly in PI individuals.Clinical trial registrationThis research study was registered at clinicaltrials.gov NCT03794050

scholarly journals THIRST RESPONSE TO POST-EXERCISE FLUID REPLACEMENT NEEDS AND CONTROLLED DRINKING

2016 ◽  
Vol 14 (2) ◽  
pp. 1-16
Author(s):  
Catalina Capitán-Jiménez ◽  
Luis Fernando Aragón-Vargas
Keyword(s):  
Plasma Volume ◽  
Repeated Measures ◽  
Fluid Replacement ◽  
Water Volume ◽  
Volume Changes ◽  
Physically Active ◽  
Post Exercise ◽  
Repeated Measures Design ◽  
Controlled Drinking ◽  
Before And After

Perceived thirst (TP) was evaluated as a dependent variable: can it distinguish among several levels of acute dehydration, is it reliable, and how does it respond to the ingestion of a fixed water volume post exercise? In a repeated-measures design, eight physically active students (24.5±3.6 years, mean±SD), reported to the laboratory on four non-consecutive days. They remained at rest or exercised at 32±3°C db and 65±6% rh to a randomly assigned dehydration equivalent to 1, 2, and 3% of body mass (BM). Following exercise, participants ingested a fixed water volume of 1.20% BM in 30 minutes; urine output, TP and plasma volume changes were assessed every 30 minutes over 3 hours. Post-exercise TP was not different before and after showering (p = 0.860), but it was significantly different among conditions (TP = 2.50 ± 0.45, 4.44 ± 0.72, 6.38 ± 0.82, and 8.63 ± 0.18 for 0, 1, 2, and 3% BM, p = 0.001). TP was associated with net fluid balance (rpart = -0.62, p < 0.0001) but, soon after drinking, TP was the same regardless of dehydration (p>0.05). Thirst perception is valid and reliable in the absence of drinking but it responds inappropriately to water intake.

scholarly journals Reliability of the Urine Lactate Concentration After Alternating-Intensity Interval Exercise

Proceedings ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 1 ◽  
Author(s):  
Ioannis Kosmidis ◽  
Stefanos Nikolaidis ◽  
Alexandros Chatzis ◽  
Kosmas Christoulas ◽  
Thomas Metaxas ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Submaximal Exercise ◽  
Physically Active ◽  
Post Exercise ◽  
Interval Exercise ◽  
Average Value ◽  
Ad Libitum ◽  
Active Adults

Aim: Our previous studies have shown that the post-exercise urine lactate concentration is a reliable exercise biomarker under controlled post-exercise hydration conditions. However, the reliability of the urine lactate concentration has been examined only after brief maximal exercise. As a result, there is no information about the reliability of this biomarker after prolonged submaximal exercise. Thus, the aim of the present study was to examine the reliability of the urine lactate concentration after interval exercise of alternating intensity under controlled or ad libitum hydration during exercise. Material & Method: Twenty-eight physically active adults (16 men and 12 women) performed three identical 45-min running tests (2 sets of 22.5 min with 3 min rest interval) on the treadmill with alternating speed and inclination at 19–24 °C, spaced three days apart. The participants drank the same amount of water during exercise in two of tests and ad libitum in the other test, in random, counterbalanced order. Blood samples were collected before exercise and 1, 3, as well as 5 min post-exercise. The highest lactate value among the post-exercise samples of each individual was recorded as his/her peak post-exercise value. Urine samples were collected before exercise and 10 as well as 60 min post-exercise and the average value of the post-exercise samples was recorded. Blood and urine lactate were analyzed spectrophotometrically. Results: The peak post-exercise blood lactate concentration was 5.5 1.7 mmol/L (mean SD throughout) for men and 4.7 1.8 mmol/L for women. The post-exercise urine lactate concentration was 1.6 1.0 mmol/L for men and 1.5 1.0 mmol/L for women. The reliability of the blood lactate concentration at the three tests was high (ICC 077–0.88), being higher under controlled hydration. However, the reliability of the urine lactate concentration was low or non-significant (ICC 0.29–0.36). Conclusions: The urine lactate concentration after prolonged submaximal exercise was lower than the corresponding blood lactate concentration and showed unsatisfactory reliability regardless of the hydration pattern during exercise. Thus, it cannot be used as a biomarker for this kind of exercise.

Endurance training fails to inhibit skeletal muscle glucose uptake during exercise

1994 ◽  
Vol 76 (5) ◽  
pp. 1876-1881 ◽  
Author(s):  
K. D. Sumida ◽  
C. M. Donovan
Keyword(s):  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Endurance Training ◽  
Plasma Glucose ◽  
Tibialis Anterior ◽  
Glycogen Content ◽  
Liver Glycogen ◽  
Glycogen Depletion ◽  
Post Exercise ◽  
Skeletal Muscle Glucose Uptake

The effects of endurance training (running 30 m/min, 10% grade for 90 min, 5 days/wk for 12 wk) on skeletal muscle glucose uptake during steady-state exercise (running 20 m/min) were studied in fed rats. A bolus injection of 2-[1,2–3H]deoxyglucose was administered to assess the glucose metabolic index (R′g), an indicator of glucose uptake, in individual tissues of the animal. After 55 min of rest or moderate exercise, various tissues were analyzed for accumulation of phosphorylated 2-[1,2–3H]-deoxyglucose and/or glycogen content. No differences were observed between groups in the resting glycogen content for any of the muscle samples examined. Resting plasma glucose concentrations were not significantly different between groups. Furthermore, no significant differences were observed in R′g between groups for any of the muscle examined (tibialis anterior, extensor digitorum longus, soleus, white gastrocnemius, red gastrocnemius). During exercise, plasma glucose concentrations were not significantly different between groups. Exercise significantly elevated R′g above resting values in the tibialis anterior (5-fold), soleus (3-fold), and red gastrocnemius (7.5-fold). Despite an elevated R′g for specific muscles during exercise, no significant differences were observed in glucose uptake between groups for any tissue examined. Concomitantly, trained animals exhibited significantly less muscle glycogen depletion during exercise compared with control animals. Liver glycogen levels were also significantly higher post-exercise in trained vs. control animals.(ABSTRACT TRUNCATED AT 250 WORDS)

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