scholarly journals Plasma BCAA concentrations during exercise of varied intensities in young healthy men—the impact of endurance training

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10491
Author(s):  
Anna Gawedzka ◽  
Marcin Grandys ◽  
Krzysztof Duda ◽  
Justyna Zapart-Bukowska ◽  
Jerzy A. Zoladz ◽  
...  
Keyword(s):  
Amino Acids ◽  
Endurance Training ◽  
Exercise Intensity ◽  
Energy Homeostasis ◽  
Lactate Concentration ◽  
Incremental Exercise ◽  
Moderate Intensity ◽  
Healthy Men ◽  
Before And After ◽  
The Impact

Background Branched-chain amino acids (BCAA) i.e., leucine (Leu), isoleucine (Ile) and valine (Val) are important amino acids, which metabolism play a role in maintaining system energy homeostasis at rest and during exercise. As recently shown lowering of circulating BCAA level improves insulin sensitivity and cardiac metabolic health. However, little is known concerning the impact of a single bout of incremental exercise and physical training on the changes in blood BCAA. The present study aimed to determine the impact of a gradually increasing exercise intensity—up to maximal oxygen uptake (VO2max) on the changes of the plasma BCAA [∑BCAA]pl, before and after 5-weeks of moderate-intensity endurance training (ET). Methods Ten healthy young, untrained men performed an incremental cycling exercise test up to exhaustion to reach VO2max, before and after ET. Results We have found that exercise of low-to-moderate intensity (up to ∼50% of VO2max lasting about 12 min) had no significant effect on the [∑BCAA]pl, however the exercise of higher intensity (above 70% of VO2max lasting about 10 min) resulted in a pronounced decrease (p < 0.05) in [∑BCAA]pl. The lowering of plasma BCAA when performing exercise of higher intensity was preceded by a significant increase in plasma lactate concentration, showing that a significant attenuation of BCAA during incremental exercise coincides with exercise-induced acceleration of glycogen utilization. In addition, endurance training, which significantly increased power generating capabilities at VO2max (p = 0.004) had no significant impact on the changes of [∑BCAA]pl during this incremental exercise. Conclusion We have concluded that an exercise of moderate intensity of relatively short duration generally has no effect on the [∑BCAA]pl in young, healthy men, whereas significant decrease in [∑BCAA]pl occurs when performing exercise in heavy-intensity domain. The impact of exercise intensity on the plasma BCAA concentration seems to be especially important for patients with cardiometabolic risk undertaken cardiac rehabilitation or recreational activity.

Blood Lactate Diagnostics in Exercise Testing and Training

2011 ◽  
Vol 6 (1) ◽  
pp. 8-24 ◽  
Author(s):  
Ralph Beneke ◽  
Renate M. Leithäuser ◽  
Oliver Ochentel
Keyword(s):  
Endurance Training ◽  
Blood Lactate ◽  
Exercise Intensity ◽  
Aerobic Power ◽  
Lactate Concentration ◽  
Metabolic Energy ◽  
Moderate Intensity ◽  
Threshold Intensity ◽  
Work Intensity ◽  
Intensity Training

A link between lactate and muscular exercise was seen already more than 200 years ago. The blood lactate concentration (BLC) is sensitive to changes in exercise intensity and duration. Multiple BLC threshold concepts define different points on the BLC power curve during various tests with increasing power (INCP). The INCP test results are affected by the increase in power over time. The maximal lactate steady state (MLSS) is measured during a series of prolonged constant power (CP) tests. It detects the highest aerobic power without metabolic energy from continuing net lactate production, which is usually sustainable for 30 to 60 min. BLC threshold and MLSS power are highly correlated with the maximum aerobic power and athletic endurance performance. The idea that training at threshold intensity is particularly effective has no evidence. Three BLC-orientated intensity domains have been established: (1) training up to an intensity at which the BLC clearly exceeds resting BLC, light- and moderate-intensity training focusing on active regeneration or high-volume endurance training (Intensity < Threshold); (2) heavy endurance training at work rates up to MLSS intensity (Threshold ≤ Intensity ≤ MLSS); and (3) severe exercise intensity training between MLSS and maximum oxygen uptake intensity mostly organized as interval and tempo work (Intensity > MLSS). High-performance endurance athletes combining very high training volume with high aerobic power dedicate 70 to 90% of their training to intensity domain 1 (Intensity < Threshold) in order to keep glycogen homeostasis within sustainable limits.

scholarly journals Effect of Adherence to Physical Exercise on Cardiometabolic Profile in Postmenopausal Women

2021 ◽  
Vol 18 (2) ◽  
pp. 656
Author(s):  
Valentina Bucciarelli ◽  
Francesco Bianco ◽  
Francesco Mucedola ◽  
Andrea Di Blasio ◽  
Pascal Izzicupo ◽  
...  
Keyword(s):  
Physical Exercise ◽  
Diastolic Function ◽  
Postmenopausal Women ◽  
Serum Glucose ◽  
Moderate Intensity ◽  
Adherence Rate ◽  
Before And After ◽  
Estrogen Depletion ◽  
The Impact ◽  
Cardiometabolic Profile

Background: Menopause is associated with negative cardiovascular adaptations related to estrogen depletion, which could be counteracted by physical exercise (PhE). However, the impact of total adherence-rate (TA) to PhE and sedentary time (SedT) on cardiometabolic profile in this population has not been elucidated. Methods: For 13-weeks, 43 women (57.1 ± 4.7 years) participated in a 4-days-a-week moderate-intensity walking training. They underwent laboratory, anthropometric and echocardiographic assessment, before and after training (T0–T1). Spontaneous physical activity (PhA) was assessed with a portable multisensory device. The sample was divided according to TA to PhE program: <70% (n = 17) and ≥70% (n = 26). Results: TA ≥ 70% group experienced a significant T1 improvement of relative wall thickness (RWT), diastolic function, VO2max, cortisol, cortisol/dehydroandrostenedione-sulphate ratio and serum glucose. After adjusting for SedT and 10-min bouts of spontaneous moderate-to-vigorous PhA, TA ≥ 70% showed the most significant absolute change of RWT and diastolic function, body mass index, weight and cortisol. TA ≥ 70% was major predictor of RWT and cortisol improvement. Conclusions: In a group of untrained, postmenopausal women, a high TA to a 13-weeks aerobic PhE program confers a better improvement in cardiometabolic profile, regardless of SedT and PhA levels.

scholarly journals Endurance Training Regulates Expression of Some Angiogenesis-Related Genes in Cardiac Tissue of Experimentally Induced Diabetic Rats

Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 498
Author(s):  
Mojdeh Khajehlandi ◽  
Lotfali Bolboli ◽  
Marefat Siahkuhian ◽  
Mohammad Rami ◽  
Mohammadreza Tabandeh ◽  
...  
Keyword(s):  
Gene Expression ◽  
Endurance Training ◽  
Molecular Mechanisms ◽  
Cardiac Tissue ◽  
Critical Role ◽  
Diabetic Rats ◽  
Moderate Intensity ◽  
Pcr Analysis ◽  
Cardiac Tissues ◽  
The Impact

Exercise can ameliorate cardiovascular dysfunctions in the diabetes condition, but its precise molecular mechanisms have not been entirely understood. The aim of the present study was to determine the impact of endurance training on expression of angiogenesis-related genes in cardiac tissue of diabetic rats. Thirty adults male Wistar rats were randomly divided into three groups (N = 10) including diabetic training (DT), sedentary diabetes (SD), and sedentary healthy (SH), in which diabetes was induced by a single dose of streptozotocin (50 mg/kg). Endurance training (ET) with moderate-intensity was performed on a motorized treadmill for six weeks. Training duration and treadmill speed were increased during five weeks, but they were kept constant at the final week, and slope was zero at all stages. Real-time polymerase chain reaction (RT-PCR) analysis was used to measure the expression of myocyte enhancer factor-2C (MEF2C), histone deacetylase-4 (HDAC4) and Calmodulin-dependent protein kinase II (CaMKII) in cardiac tissues of the rats. Our results demonstrated that six weeks of ET increased gene expression of MEF2C significantly (p < 0.05), and caused a significant reduction in HDAC4 and CaMKII gene expression in the DT rats compared to the SD rats (p < 0.05). We concluded that moderate-intensity ET could play a critical role in ameliorating cardiovascular dysfunction in a diabetes condition by regulating the expression of some angiogenesis-related genes in cardiac tissues.

Ten-day endurance training attenuates the hyperosmotic suppression of cutaneous vasodilation during exercise but not sweating

2005 ◽  
Vol 99 (1) ◽  
pp. 237-243 ◽  
Author(s):  
Takashi Ichinose ◽  
Kazunobu Okazaki ◽  
Shizue Masuki ◽  
Hiroyuki Mitono ◽  
Mian Chen ◽  
...  
Keyword(s):  
Endurance Training ◽  
Exercise Intensity ◽  
Plasma Osmolality ◽  
Young Male ◽  
Cycle Ergometer ◽  
Peak Oxygen Consumption ◽  
Cutaneous Vasodilation ◽  
Thermoregulatory Responses ◽  
Before And After ◽  
The Individual

It is well known that hyperosmolality suppresses thermoregulatory responses and that plasma osmolality (Posmol) increases with exercise intensity. We examined whether the decreased esophageal temperature thresholds for cutaneous vasodilation (THFVC) and sweating (THSR) after 10-day endurance training (ET) are caused by either attenuated increase in Posmol at a given exercise intensity or blunted sensitivity of hyperosmotic suppression. Nine young male volunteers exercised on a cycle ergometer at 60% peak oxygen consumption rate (V̇o2 peak) for 1 h/day for 10 days at 30°C. Before and after ET, thermoregulatory responses were measured during 20-min exercise at pretraining 70% V̇o2 peak in the same environment as during ET under isoosmotic or hyperosmotic conditions. Hyperosmolality by ∼10 mosmol/kgH2O was attained by acute hypertonic saline infusion. After ET, V̇o2 peak and blood volume (BV) both increased by ∼4% ( P < 0.05), followed by a decrease in THFVC ( P < 0.05) but not by that in THSR. Although there was no significant decrease in Posmol at the thresholds after ET, the sensitivity of increase in THFVC at a given increase in Posmol [ΔTHFVC/ΔPosmol,°C·(mosmol/kgH2O)−1], determined by hypertonic infusion, was reduced to 0.021 ± 0.005 from 0.039 ± 0.004 before ET ( P < 0.05). The individual reductions in ΔTHFVC/ΔPosmol after ET were highly correlated with their increases in BV around THFVC ( r = −0.89, P < 0.005). In contrast, there was no alteration in the sensitivity of the hyperosmotic suppression of sweating after ET. Thus the downward shift of THFVC after ET was partially explained by the blunted sensitivity to hyperosmolality, which occurred in proportion to the increase in BV.

scholarly journals The impact of Hayward green kiwifruit on dietary protein digestion and protein metabolism

2020 ◽  
Author(s):  
Sanghee Park ◽  
David D. Church ◽  
Carlene Starck ◽  
Scott E. Schutzler ◽  
Gohar Azhar ◽  
...  
Keyword(s):  
Amino Acids ◽  
Dietary Protein ◽  
Protein Metabolism ◽  
Plasma Concentrations ◽  
Whole Body ◽  
Protein Digestion ◽  
Body Protein ◽  
Before And After ◽  
The Impact ◽  
Green Kiwifruit

Abstract Purpose The purpose of the study was to determine if an actinidin protease aids gastric digestion and the protein anabolic response to dietary protein. Methods Hayward green kiwifruit (containing an actinidin protease) and Hort 16A gold kiwifruit (devoid of actinidin protease) were given in conjunction with a beef meal to healthy older subjects. Twelve healthy older males (N = 6) and females (N = 6) were studied with a randomized, double-blinded, crossover design to assess muscle and whole-body protein metabolism before and after ingestion of kiwifruit and 100 g of ground beef. Subjects consumed 2 of each variety of kiwifruit daily for 14 d prior to each metabolic study, and again during each study with beef intake. Results Hayward green kiwifruit consumption with beef resulted in a more rapid increase in peripheral plasma essential amino acid concentrations. There were significant time by kiwifruit intake interactions for plasma concentrations of EAAs, branched chain amino acids (BCAAs), and leucine (P < 0.01). However, there was no difference in the total amount of EAAs absorbed. As a result, there were no differences between kiwifruit in any of the measured parameters of protein kinetics. Conclusion Consumption of Hayward green kiwifruit, with a beef meal facilitates protein digestion and absorption of the constituent amino acids as compared to Hort 16A gold kiwifruit. Clinical trial NCT04356573, April 21, 2020 “retrospectively registered”.

Role of d-serine in the beneficial effects of repetitive transcranial magnetic stimulation in post-stroke patients

2020 ◽  
Vol 32 (3) ◽  
pp. 128-134 ◽  
Author(s):  
Masachika Niimi ◽  
Yuko Fujita ◽  
Tamaki Ishima ◽  
Kenji Hashimoto ◽  
Nobuyuki Sasaki ◽  
...  
Keyword(s):  
Amino Acids ◽  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Stroke Patients ◽  
Post Stroke ◽  
Beneficial Effects ◽  
Depressed Patients ◽  
Before And After ◽  
The Impact

AbstractObjective:Abnormalities in neurotransmission via N-methyl-d-aspartic acid receptor (NMDAR) play a role in the pathophysiology of neuropsychiatric disorders. The impact of repetitive transcranial magnetic stimulation (rTMS) on NMDAR-related amino acids remains unknown. We aim to investigate the effects of rTMS on NMDAR-related amino acids in serum of post-stroke patients.Methods:Ninety-five consecutive post-stroke patients with upper limb hemiparesis were recruited. In 27 patients, the Beck Depression Inventory (BDI) score was 10 or higher. Twelve depressed patients underwent rehabilitation in combination with rTMS and 15 non-depressed patients underwent rehabilitation only without rTMS for 14 days. 1 Hz rTMS was applied to the primary motor area in the non-lesional hemisphere. BDI was conducted before and after treatment. Serum glutamine, glutamate, glycine, l-serine, and d-serine levels were measured before and after treatment.Results:There were no differences between depressed patients and non-depressed patients in clinical characteristics, levels of the five amino acids in serum, and the ratio of amino acids. However, in 27 depressed patients, there was a significant correlation between levels of glutamate in serum and BDI (ρ = 0.428, p = 0.026). BDI decreased significantly in depressed patients after treatment with or without rTMS. d-serine decreased in the rehabilitation with rTMS group, but increased in the rehabilitation without rTMS group. l-serine increased in the rehabilitation with rTMS group, but decreased in the rehabilitation without rTMS group.Conclusion:The results suggest that rTMS can modulate NMDAR-related amino acids in blood, producing beneficial effects.

Balance of carbohydrate and lipid utilization during exercise: the "crossover" concept

1994 ◽  
Vol 76 (6) ◽  
pp. 2253-2261 ◽  
Author(s):  
G. A. Brooks ◽  
J. Mercier
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Lipid Oxidation ◽  
Endurance Training ◽  
Exercise Intensity ◽  
Fiber Type ◽  
Moderate Intensity ◽  
Induced Responses ◽  
O2 Uptake ◽  
Sympathetic Nervous

The “crossover” concept represents a theoretical means by which one can understand the effects of exercise intensity and prior endurance training on the balance of carbohydrate (CHO) and lipid metabolism during sustained exercise. According to the crossover concept, endurance training results in muscular biochemical adaptations that enhance lipid oxidation as well as decrease the sympathetic nervous system responses to given submaximal exercise stresses. These adaptations promote lipid oxidation during mild- to moderate-intensity exercise. In contrast, increases in exercise intensity are conceived to increase contraction-induced muscle glycogenolysis, alter the pattern of fiber type recruitment, and increase sympathetic nervous system activity. Therefore the pattern of substrate utilization in an individual at any point in time depends on the interaction between exercise intensity-induced responses (which increase CHO utilization) and endurance training-induced responses (which promote lipid oxidation). The crossover point is the power output at which energy from CHO-derived fuels predominates over energy from lipids, with further increases in power eliciting a relative increment in CHO utilization and a decrement in lipid oxidation. The contemporary literature contains data indicating that, after endurance training, exercise at low intensities (< or = 45% maximal O2 uptake) is accomplished with lipid as the main substrate. In contrast, the literature also contains reports that are interpreted to indicate that during hard-intensity exercise (approximately 75% maximal O2 uptake) CHO is the predominant substrate. Seen within the context of the crossover concept these apparently divergent results are, in fact, consistent.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Effect of Combined Endurance Training and MitoQ on Cardiac Function and Serum Level of Antioxidants, NO, miR-126, and miR-27a in Hypertensive Individuals

2022 ◽  
Vol 2022 ◽  
pp. 1-13
Author(s):  
Yaser Masoumi-Ardakani ◽  
Hamid Najafipour ◽  
Hamid Reza Nasri ◽  
Soheil Aminizadeh ◽  
Shirin Jafari ◽  
...  
Keyword(s):  
Cardiac Function ◽  
Endurance Training ◽  
Cardiovascular Health ◽  
Serum Levels ◽  
Cycle Ergometer ◽  
Moderate Intensity ◽  
Double Blind ◽  
Treatment Groups ◽  
Before And After ◽  
And Control

Objectives. Hypertension (HTN) is one of the most important risk factors for cardiovascular diseases. Despite advances in treatment and control of HTN, the prevalence of HTN is still increasing. MitoQ is a supplement that acts on mitochondria and attenuates reactive oxygen species (ROS), which plays an important role in cardiovascular health. miRNAs play an important role in the pathophysiology of HTN. We evaluated the effects of MitoQ supplementation and endurance training (ET), alone and in combination, on functional indices of the heart and serum levels of miR-126, miR-27a, antioxidants, and NO, in patients with HTN. Methods. In a double-blind randomized clinical trial, 52 male participants (age 40-55 years) were randomly divided into four groups ( n = 13 ) of placebo, MitoQ (20 mg/day, oral), ET (cycle ergometer, moderate intensity, 40-60% VO2 peak, heart rate 120-140 b/min, 45 min a day, three days/week for six weeks), and MitoQ+ET. Cardiac function indices were assessed by echocardiography before and after interventions. Results. Systolic blood pressure (SBP) significantly decreased in all intervention groups ( P < 0.001 ) while DBP ( P < 0.01 ) and LV hypertrophy ( P < 0.05 ) were significantly decreased only in the MitoQ+ET group. Serum levels of SOD, GPx, and NO and the level of miR-126 significantly increased in all treatment groups, while miR-27a reduced in the ET ( P < 0.05 ) and MitoQ+ET ( P < 0.01 ) groups. Conclusions. Compared to MitoQ and ET alone, their combination has more prominent improving effects on cardiac health and amelioration of BP in the patients with HTN. These effects are through miR-126 and miR-27a modulation and ameliorating mitochondrial ROS production.

scholarly journals Gluconeogenesis and hepatic glycogenolysis during exercise at the lactate threshold

2013 ◽  
Vol 114 (3) ◽  
pp. 297-306 ◽  
Author(s):  
Chi-An W. Emhoff ◽  
Laurent A. Messonnier ◽  
Michael A. Horning ◽  
Jill A. Fattor ◽  
Thomas J. Carlson ◽  
...  
Keyword(s):  
Endurance Training ◽  
Exercise Intensity ◽  
Lactate Threshold ◽  
Lactate Concentration ◽  
Glucose Production ◽  
Constant Load ◽  
Metabolic Clearance ◽  
Trained Subjects ◽  
Relative Exercise Intensity ◽  
Constant Load Exercise

Because the maintenance of glycemia is essential during prolonged exercise, we examined the effects of endurance training, exercise intensity, and plasma lactate concentration ([lactate]) on gluconeogenesis (GNG) and hepatic glycogenolysis (GLY) in fasted men exercising at, and just below, the lactate threshold (LT), where GNG precursor lactate availability is high. Twelve healthy men (6 untrained, 6 trained) completed 60 min of constant-load exercise at power outputs corresponding to their individual LT. Trained subjects completed two additional 60-min sessions of constant-load exercise: one at 10% below the LT workload (LT-10%), and the other with a lactate clamp (LT-10%+LC) to match the [lactate] of the LT trial. Flux rates were determined by primed continuous infusion of [6,6-2H2]glucose, [3-13C]lactate, and [13C]bicarbonate tracers during 90 min of rest and 60 min of cycling. Exercise at LT corresponded to 67.6 ± 1.3 and 74.8 ± 1.7% peak O2 consumption in the untrained and trained subjects, respectively ( P < 0.05). Relative exercise intensity was matched between the untrained group at LT and the trained group at LT-10%, and [lactate] during exercise was matched in the LT and LT-10%+LC trials via exogenous lactate infusion. Glucose kinetics (rate of appearance, rate of disposal, and metabolic clearance rate) were augmented with the lactate clamp. GNG was decreased in the trained subjects exercising at LT and LT-10% compared with the untrained subjects, but increasing [lactate] in the LT-10%+LC trial significantly increased GNG (4.4 ± 0.9 mg·kg−1·min−1) compared with its corresponding control (1.7 ± 0.4 mg·kg−1·min−1, P < 0.05). Hepatic GLY was higher in the trained than untrained subjects, but not significantly different across conditions. We conclude that GNG plays an essential role in maintaining total glucose production during exercise in fasted men, regardless of training state. However, endurance training increases the ability to achieve a higher relative exercise intensity and absolute power output at the LT without a significant decrease in GNG. Furthermore, raising systemic precursor substrate availability increases GNG during exercise, but not at rest.

Does Polarized Training Improve Performance in Recreational Runners?

2014 ◽  
Vol 9 (2) ◽  
pp. 265-272 ◽  
Author(s):  
Iker Muñoz ◽  
Stephen Seiler ◽  
Javier Bautista ◽  
Javier España ◽  
Eneko Larumbe ◽  
...  
Keyword(s):  
Training Program ◽  
Endurance Training ◽  
High Intensity ◽  
Ventilatory Threshold ◽  
Training Session ◽  
Moderate Intensity ◽  
Intervention Period ◽  
Low Intensity ◽  
Recreational Runners ◽  
The Impact

Purpose:To quantify the impact of training-intensity distribution on 10K performance in recreational athletes.Methods:30 endurance runners were randomly assigned to a training program emphasizing low-intensity, sub-ventilatory-threshold (VT), polarized endurance-training distribution (PET) or a moderately high-intensity (between-thresholds) endurance-training program (BThET). Before the study, the subjects performed a maximal exercise test to determine VT and respiratory-compensation threshold (RCT), which allowed training to be controlled based on heart rate during each training session over the 10-wk intervention period. Subjects performed a 10-km race on the same course before and after the intervention period. Training was quantified based on the cumulative time spent in 3 intensity zones: zone 1 (low intensity, <VT), zone 2 (moderate intensity, between VT and RCT), and zone 3 (high intensity, >RCT). The contribution of total training time in each zone was controlled to have more low-intensity training in PET (±77/3/20), whereas for BThET the distribution was higher in zone 2 and lower in zone 1 (±46/35/19).Results:Both groups significantly improved their 10K time (39min18s ± 4min54s vs 37min19s ± 4min42s, P < .0001 for PET; 39min24s ± 3min54s vs 38min0s ± 4min24s, P < .001 for BThET). Improvements were 5.0% vs 3.6%, ~41 s difference at post-training-intervention. This difference was not significant. However, a subset analysis comparing the 12 runners who actually performed the most PET (n = 6) and BThET (n = 16) distributions showed greater improvement in PET by 1.29 standardized Cohen effect-size units (90% CI 0.31–2.27, P = .038).Conclusions:Polarized training can stimulate greater training effects than between-thresholds training in recreational runners.

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