Pre-exercise β-hydroxy-β-methylbutyrate free-acid supplementation improves work capacity recovery: a randomized, double-blinded, placebo-controlled study

2018 ◽  
Vol 43 (7) ◽  
pp. 691-696 ◽  
Author(s):  
Ana Luiza Matias Correia ◽  
Filipe Dinato de Lima ◽  
Martim Bottaro ◽  
Amilton Vieira ◽  
Andrew Correa da Fonseca ◽  
...  
Keyword(s):  
Single Dose ◽  
High Intensity ◽  
Time Course ◽  
Free Acid ◽  
Exercise Bout ◽  
Work Capacity ◽  
High Intensity Exercise ◽  
Controlled Study ◽  
Exercise Protocol ◽  
Young Males

The purpose of this study was to investigate the effects of a single-dose of β-hydroxy-β-methylbutyrate free acid (HMB-FA) supplementation on muscle recovery after a high-intensity exercise bout. Twenty-three trained young males were randomly assigned to receive either a single-dose supplementation of 3 g of HMB-FA (n = 12; age, 22.8 ± 3.0 years) or placebo (PLA; n = 11; age, 22.9 ± 3.1 years). A muscle damage protocol was applied 60 min after supplementation, and consisted of 7 sets of 20 drop jumps from a 60-cm box with 2-min rest intervals between sets. Muscle swelling, countermovement jump (CMJ), maximal voluntary isometric torque (MVIT), and work capacity (WC) were measured before, immediately after, and 24, 48, and 72 h after the exercise protocol. Muscle swelling, CMJ, and MVIT changed similarly in both groups after the exercise protocol (p < 0.001), but returned to pre-exercise levels after 24 h in both groups. WC decreased similarly in both groups after the exercise protocol (p < 0.01). For HMB-FA, WC returned to pre-exercise level 24 h after exercise protocol. However, for PLA, WC did not return to pre-exercise level even 72 h after the exercise protocol. In summary, a single-dose of HMB-FA supplementation improved WC recovery after a high-intensity exercise bout. However, HMB-FA did not affect the time-course of muscle swelling, MVIT, and CMJ recovery.

Recovery of Cycling Gross Efficiency After Time-Trial Exercise

2018 ◽  
Vol 13 (8) ◽  
pp. 1028-1033 ◽  
Author(s):  
Sjors Groot ◽  
Lars H.J. van de Westelaken ◽  
Dionne A. Noordhof ◽  
Koen Levels ◽  
Jos J. de Koning
Keyword(s):  
High Intensity ◽  
Time Course ◽  
Time Trial ◽  
Exercise Bout ◽  
Submaximal Exercise ◽  
High Intensity Exercise ◽  
Cycling Exercise ◽  
Gross Efficiency ◽  
Before And After ◽  
The Difference

Background: Research has shown that gross efficiency (GE) declines during high-intensity exercise, but the time course of recovery of GE after high-intensity exercise has not yet been investigated. Purpose: To determine the time course of the recovery of GE after time trials (TTs) of different lengths. Methods: Nineteen trained male cyclists participated in this study. Before and after TTs of 2000 and 20,000 m, subjects performed submaximal exercise at 55% of the power output attained at maximal oxygen uptake (PVO2max). The postmeasurement continued until 30 min after the end of the TT, during which GE was determined over 3-min intervals. The magnitude-based-inferences approach was used for statistical analysis. Results: GE decreased substantially during the 2000-m and 20,000-m TTs (−11.8% [3.6%] and −6.2% [4.0%], respectively). A most likely and very likely recovery of GE was found during the first half of the submaximal exercise bout performed after the 2000-m, with only a possible increase in GE during the first part of the submaximal exercise bout performed after the 20,000-m. After both distances, GE did not fully recover to the initial pre-TT values, as the difference between the pre-TT value and average GE value of minutes 26–29 was still most likely negative for both the 2000- and 20,000-m (−6.1% [2.8%] and −7.0% [4.5%], respectively). Conclusions: It is impossible to fully recover GE after TTs of 2000- or 20,000-m during 30 min of submaximal cycling exercise performed at an intensity of 55% PVO2max.

scholarly journals High-intensity exercise acutely decreases the membrane content of MCT1 and MCT4 and buffer capacity in human skeletal muscle

2007 ◽  
Vol 102 (2) ◽  
pp. 616-621 ◽  
Author(s):  
David Bishop ◽  
Johann Edge ◽  
Claire Thomas ◽  
Jacques Mercier
Keyword(s):  
Relative Abundance ◽  
High Intensity ◽  
Time Course ◽  
Vastus Lateralis ◽  
Exercise Bout ◽  
High Intensity Exercise ◽  
Transport Systems ◽  
Western Blots ◽  
Induced Changes

The regulation of intracellular pH during intense muscle contractions occurs via a number of different transport systems [e.g., monocarboxylate transporters (MCTs)] and via intracellular buffering (βmin vitro). The aim of this study was to investigate the effects of an acute bout of high-intensity exercise on both MCT relative abundance and βmin vitro in humans. Six active women volunteered for this study. Biopsies of the vastus lateralis were obtained at rest and immediately after 45 s of exercise at 200% of maximum O2 uptake. βmin vitro was determined by titration, and MCT relative abundance was determined in membrane preparations by Western blots. High-intensity exercise was associated with a significant decrease in both MCT1 (−24%) and MCT4 (−26%) and a decrease in βmin vitro (−11%; 135 ± 3 to 120 ± 2 μmol H+·g dry muscle−1·pH−1; P < 0.05). These changes were consistently observed in all subjects, and there was a significant correlation between changes in MCT1 and MCT4 relative abundance ( R2 = 0.92; P < 0.05). In conclusion, a single bout of high-intensity exercise decreased both MCT relative abundance in membrane preparations and βmin vitro. Until the time course of these changes has been established, researchers should consider the possibility that observed training-induced changes in MCT and βmin vitro may be influenced by the acute effects of the last exercise bout, if the biopsy is taken soon after the completion of the training program. The implications that these findings have for lactate (and H+) transport following acute, exhaustive exercise warrant further investigation.

scholarly journals A Short Bout of High-intensity Exercise Alters Ipsilesional Motor Cortical Excitability Post-stroke

2019 ◽  
Author(s):  
Xin Li ◽  
Charalambos C. Charalambous ◽  
Darcy S. Reisman ◽  
Susanne M. Morton
Keyword(s):  
High Intensity ◽  
Acute Exercise ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
High Intensity Exercise ◽  
Exercise Protocol ◽  
Post Stroke ◽  
Motor Cortical Excitability ◽  
Motor Cortical ◽  
Lactate Levels

AbstractBackgroundAcute exercise can increase motor cortical excitability and enhance motor learning in healthy individuals, an effect known as exercise priming. Whether it has the same effects in people with stroke is unclear.ObjectivesThe objective of this study was to investigate whether a short, clinically-feasible high-intensity exercise protocol can increase motor cortical excitability in non-exercised muscles of chronic stroke survivors.MethodsThirteen participants with chronic, unilateral stroke participated in two sessions, at least one week apart, in a crossover design. In each session, they underwent either high-intensity lower extremity exercise or quiet rest. Motor cortical excitability of the extensor carpi radialis muscles was measured bilaterally with transcranial magnetic stimulation before and immediately after either exercise or rest. Motor cortical excitability changes (post-exercise or rest measures normalized to pre-test measures) were compared between exercise vs. rest conditions.ResultsAll participants were able to reach the target high-intensity exercise level. Blood lactate levels increased significantly after exercise (p < 0.001, d = 2.85). Resting motor evoked potentials from the lesioned hemisphere increased after exercise compared to the rest condition (p = 0.046, d = 2.76), but this was not the case for the non-lesioned hemisphere (p = 0.406, d = 0.25).ConclusionsHigh-intensity exercise can increase lesioned hemisphere motor cortical excitability in a non-exercised muscle post-stroke. Our short and clinically-feasible exercise protocol shows promise as a potential priming method in stroke rehabilitation.

β-Hydroxy-β-methylbutyrate (HMB)-free acid attenuates circulating TNF-α and TNFR1 expression postresistance exercise

2013 ◽  
Vol 115 (8) ◽  
pp. 1173-1182 ◽  
Author(s):  
Jeremy R. Townsend ◽  
Maren S. Fragala ◽  
Adam R. Jajtner ◽  
Adam M. Gonzalez ◽  
Adam J. Wells ◽  
...  
Keyword(s):  
Recovery Time ◽  
Cold Water ◽  
Free Acid ◽  
Water Immersion ◽  
Exercise Bout ◽  
Cold Water Immersion ◽  
Intense Exercise ◽  
Exercise Protocol ◽  
Percent Change ◽  
Tnf Α

The purpose of this study was to examine the effect of β-hydroxy-β-methylbutyrate-free acid (HMB-FA) and cold-water immersion (CWI) on circulating concentrations of TNF-α and monocyte TNF-α receptor 1 (TNFR1) expression. Forty resistance-trained men (22.3 ± 2.4 yr) were randomized into four groups [placebo (PL), HMB-FA, CWI, and HMB-FA-CWI] and performed an acute, intense exercise protocol (four sets of up to 10 repetitions of the squat, dead lift, and split squat). Participants also performed four sets of up to 10 repetitions of the squat at 24 and 48 h following the initial exercise bout. Blood was sampled before exercise (PRE), immediately postexercise (IP), and 30 min, 24 h, and 48 h postexercise (30P, 24P, and 48P, respectively). Circulating TNF-α was assayed, and TNFR1 expression on CD14+ monocytes was measured by flow cytometry. The exercise protocol significantly elevated TNF-α in only PL ( P = 0.006) and CWI ( P = 0.045) IP. Mean percent changes show that TNF-α significantly increased from PRE to IP for only PL and CWI groups ( P < 0.05), whereas the percent change of TNF-α for HMB-FA and HMB-FA-CWI was not significant. TNFR1 expression was elevated in PL ( P = 0.023) and CWI ( P = 0.02) at 30P compared with PRE, whereas both HMB-FA-treated groups did not increase significantly. In conclusion, HMB-FA attenuated circulating TNF-α IP and TNFR1 expression during recovery compared with PL and CWI. HMB-FA supplementation may attenuate the initial immune response to intense exercise, which may reduce recovery time following intense exercise.

scholarly journals High intensity exercise downregulates FTO mRNA expression during the early stages of recovery in young males and females

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Jessica Danaher ◽  
Christos G. Stathis ◽  
Robin A. Wilson ◽  
Alba Moreno-Asso ◽  
R. Mark Wellard ◽  
...  
Keyword(s):  
Mrna Expression ◽  
High Intensity ◽  
High Intensity Exercise ◽  
Young Males ◽  
Early Stages ◽  
Males And Females

TIME-COURSE CHANCES IN PHYSIOLOGIC ADAPTATIONS TO MODERATE-TO-HIGH INTENSITY EXERCISE TRAINING IN CARDIAC PATIENTS

1986 ◽  
Vol 6 (10) ◽  
pp. 434
Author(s):  
Vickie Hollingsworth ◽  
Barry Franklin ◽  
Jim Cameron ◽  
Seymour Gordon ◽  
C. Timmis Gerald
Keyword(s):  
Exercise Training ◽  
High Intensity ◽  
Time Course ◽  
High Intensity Exercise ◽  
Cardiac Patients

Time course and magnitude of fluid and electrolyte shifts during recovery from high-intensity exercise in Standardbred racehorses

2005 ◽  
Vol 2 (2) ◽  
pp. 77-87 ◽  
Author(s):  
Amanda Waller ◽  
Michael I Lindinger
Keyword(s):  
High Intensity ◽  
Time Course ◽  
Venous Blood ◽  
Recovery Period ◽  
Extracellular Fluid ◽  
Fluid Volume ◽  
High Intensity Exercise ◽  
Plasma Protein Concentration ◽  
Intracellular Fluid ◽  
Standardbred Racehorses

AbstractThe present study characterized the fluid and electrolyte shifts that occur in Standardbred racehorses during recovery from high-intensity exercise. Jugular venous blood was sampled from 13 Standardbreds in racing condition, at rest and for 2 h following a high-intensity training workout. Total body water (TBW), extracellular fluid volume (ECFV) and plasma volume (PV) were measured at rest using indicator dilution techniques (D2O, thiocyanate and Evans Blue, respectively). Changes in TBW were assessed from measures of body mass, and changes in PV and ECFV were calculated from changes in plasma protein concentration. Exercise resulted in a 26.9% decrease in PV. At 10 min of recovery TBW and ECFV were decreased by 2.2% and 16.5% respectively, while intracellular fluid volume was increased by 7.1%. There was a continued loss of fluid due to sweating throughout the recovery period such that TBW was decreased by 3.9% at 90 min of recovery. This decrease in TBW was nearly equally partitioned between the extracellular and intracellular fluid compartments. Plasma Na+ and Cl− contents were decreased at 1 min of recovery, but not different from rest by 40 min of recovery. Plasma K+ content at 1 min post exercise was not different from the pre-exercise value; however, by 5 min of recovery K+ content was significantly decreased and it remained decreased throughout the recovery period. It is concluded that there are very rapid and large fluid and electrolyte shifts between body compartments during and after high-intensity exercise, and that full recovery of these shifts requires 90–120 min.

scholarly journals The effects of a high-intensity exercise bout on landing biomechanics post anterior cruciate ligament reconstruction: a quasi-experimental study

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Ahmad Dhahawi Alanazi ◽  
Katy Mitchell ◽  
Toni Roddey ◽  
Aqeel M. Alenazi ◽  
Msaad M. Alzhrani ◽  
...  
Keyword(s):  
High Intensity ◽  
Ligament Reconstruction ◽  
Cruciate Ligament ◽  
Exercise Bout ◽  
High Intensity Exercise ◽  
Soccer Players ◽  
Cruciate Ligament Reconstruction ◽  
Landing Biomechanics ◽  
Ankle Joints ◽  
Anterior Cruciate

Abstract Background We aimed to examine the effect of a high-intensity exercise bout on landing biomechanics in soccer players who underwent anterior cruciate ligament reconstruction (ACLR) and non-injured soccer players during a soccer-specific landing maneuver. Methods Eighteen soccer players who underwent ACLR and 18 normal soccer players were enrolled in this investigation (ACLR group; age, 26.11 ± 3.95 years; body mass index, 23.52 ± 2.69 kg/m2; surgery time, 5 ± 3.30 years: control group; age, 25.83 ± 3.51 years; body mass index, 24.09 ± 3.73 kg/m2, respectively). Participants were evaluated during the landing maneuver before and after carrying out the high-intensity exercise bout using the Wingate test. The intensity of the exercise was defined as a blood lactate accumulation of at least 4 mmol/L. The dependent variables included sagittal-plane kinematics and kinetics of the ankle, knee and hip joints, and electromyography activity of the gastrocnemius, hamstrings, quadriceps, and gluteus maximus. Results On 2 × 2 analysis of variance, none of the dependent variable showed significant exercise×group interactions. Regardless of group, significant main effects of exercise were found. Post-exercise landing was characterized by increased flexion of hip (p = 0.01), knee (p = 0.001), and ankle joints (p = 0.002); increased extension moments of hip (p = 0.009), knee (p = 0.012), and ankle joints (p = 0.003), as well as decreased quadriceps activity (p = 0.007). Conclusion At 1 year or more post-ACLR, the effect of the high-intensity exercise bout on landing biomechanics is not expected to differ from that experienced by healthy soccer players.

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