Chronic and acute exercise do not alter Ca2+ regulatory  systems and ectonucleotidase activities in rat heart

The purpose of this investigation was to examine the effects of chronic and acute exercise on the main components involved in excitation-contraction coupling and relaxation in rat heart. Sixty male Wistar rats were divided into a sedentary (S) and three 12-wk treadmill-trained groups (T-1, moderate intensity; T-2, high intensity; T-3, interval running). After 12-wk, 15 rats from the S group and 15 rats from the T-2 group were subjected to a single treadmill-exercise session until exhaustion before being killed at 0, 24, or 48 h (acute exercise). The remaining animals were killed 48 h after the last standard exercise session (chronic exercise). The efficacy of the training programs was confirmed by an increase in treadmill endurance time and in skeletal muscle citrate synthase activity. None of the exercise programs modified heart weight or cardiac oxidative capacity. [3H]PN200–110 and [3H]ryanodine binding to cardiac homogenates indicated that the density of L-type and sarcoplasmic reticulum (SR) Ca2+channels was the same in S and trained rats. The SR Ca2+-ATPase activity was also unmodified. Finally, the activities of the ectoenzymes Mg2+-ATPase and 5′-nucleotidase, which are involved in degradation of extracellular nucleotides, were not affected by either of the running programs. After the acute exercise session, no changes were detected in either of the tested parameters in heart homogenates of S and T-2 animals. We conclude that neither treadmill-exercise training for 12 wk nor exhaustive exercise alters the density of Ca2+ channels involved in excitation-contraction coupling or the SR Ca2+-ATPase and the ectonucleotidase activities in rat heart.

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Acute Exercise Increases Adiponectin Levels in Abdominally Obese Men

Journal of Nutrition and Metabolism ◽

10.1155/2012/148729 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 25

Author(s):

Travis J. Saunders ◽

Andrew Palombella ◽

K. Ashlee McGuire ◽

Peter M. Janiszewski ◽

Jean-Pierre Després ◽

...

Keyword(s):

Aerobic Exercise ◽

Acute Exercise ◽

Treadmill Exercise ◽

Aerobic Exercise Training ◽

Exercise Session ◽

Short Term ◽

Acute Bout ◽

Plasma Adiponectin ◽

Peak Intensity ◽

Before And After

Objective. To examine the effect of acute and short-term (~1 week) aerobic exercise training on plasma adiponectin levels in inactive, abdominally obese men.Materials and Methods. Inactive and abdominally obese men (n=38, waist circumference ≥102 cm) recruited from Kingston, Canada were randomly allocated to perform three bouts of aerobic treadmill exercise at either low (50% VO2peak) or high (75% VO2peak) intensity during a 1-week period. Blood samples were taken before and after the first exercise session and 24–72 hours following the completion of the final exercise session.Results. Adiponectin levels were elevated immediately following an acute bout of exercise at both high and low intensities (High:5.79±0.42versus5.05±0.41 ug/mL; Low:5.24±0.44versus4.37±0.44 ug/mL,P<0.05) and remained elevated following 30 minutes of rest. In comparison to baseline, adiponectin levels were also elevated 24–72 hours following the final exercise session (High:5.47±0.48versus4.88±0.48 ug/mL; Low:5.18±0.49versus4.47±0.49 ug/mL,P<0.05).Conclusion. Both acute and short-term aerobic exercise result in a significant increase in plasma adiponectin levels in inactive, abdominally obese men independent of intensity.

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Exercise training increases branched-chain oxoacid dehydrogenase kinase content in human skeletal muscle

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00115.2007 ◽

2007 ◽

Vol 293 (3) ◽

pp. R1335-R1341 ◽

Cited By ~ 18

Author(s):

Krista R. Howarth ◽

Kirsten A. Burgomaster ◽

Stuart M. Phillips ◽

Martin J. Gibala

Keyword(s):

Skeletal Muscle ◽

Exercise Training ◽

Protein Content ◽

Human Skeletal Muscle ◽

Acute Exercise ◽

Citrate Synthase ◽

Muscle Protein ◽

Moderate Intensity ◽

Main Effect ◽

Branched Chain

The branched-chain oxoacid dehydrogenase complex (BCOAD) is rate determining for the oxidation of branched-chain amino acids (BCAAs) in skeletal muscle. Exercise training blunts the acute exercise-induced activation of BCOAD (BCOADa) in human skeletal muscle (McKenzie S, Phillips SM, Carter SL, Lowther S, Gibala MJ, Tarnopolsky MA. Am J Physiol Endocrinol Metab 278: E580–E587, 2000); however, the mechanism is unknown. We hypothesized that training would increase the muscle protein content of BCOAD kinase, the enzyme responsible for inactivation of BCOAD by phosphorylation. Twenty subjects [23 ± 1 yr; peak oxygen uptake (V̇o2peak) = 41 ± 2 ml·kg−1·min−1] performed 6 wk of either high-intensity interval or continuous moderate-intensity training on a cycle ergometer ( n = 10/group). Before and after training, subjects performed 60 min of cycling at 65% of pretraining V̇o2peak, and needle biopsy samples (vastus lateralis) were obtained before and immediately after exercise. The effect of training was demonstrated by an increased V̇o2peak, increased citrate synthase maximal activity, and reduced muscle glycogenolysis during exercise, with no difference between groups (main effects, P < 0.05). BCOADa was lower after training (main effect, P < 0.05), and this was associated with a ∼30% increase in BCOAD kinase protein content (main effect, P < 0.05). We conclude that the increased protein content of BCOAD kinase may be involved in the mechanism for reduced BCOADa after exercise training in human skeletal muscle. These data also highlight differences in models used to study the regulation of skeletal muscle BCAA metabolism, since exercise training was previously reported to increase BCOADa during exercise and decrease BCOAD kinase content in rats (Fujii H, Shimomura Y, Murakami T, Nakai N, Sato T, Suzuki M, Harris RA. Biochem Mol Biol Int 44: 1211–1216, 1998).

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The Effect of Single Bout of Acute Exercise on Working Memory Performance

Birat Journal of Health Sciences ◽

10.3126/bjhs.v3i2.20966 ◽

2018 ◽

Vol 3 (2) ◽

pp. 484-487

Author(s):

Santosh Kumar Deo ◽

Kopila Agrawal ◽

Prem Bhattrai ◽

Raju Kumar Chaudhary

Keyword(s):

Decision Making ◽

Working Memory ◽

Acute Exercise ◽

Test Procedure ◽

Step Test ◽

Moderate Intensity ◽

Exercise Session ◽

Moderate Intensity Exercise ◽

Single Bout ◽

Back Task

Introduction: Working memory is a kind of short term memory important for reasoning and guiding decision-making and behavioral process.Objective: The goal of the present research was to study the outcome of single bout of acute moderate-intensity exercise on working memory.Methodology: Twenty two male subjects were asked to perform working memory task by 2n back task in baseline resting, immediately after exercise and after five minute of exercise session. 3 minute step test procedure was used as a moderate intensity exercise intervention.Results: The percentage correctness of 2n back task of working memory was found to be 64.36% for baseline resting condition, 78.01 % for immediately after 3-minute step test and 80.70% for 5 minute after the exercise. In both exercise session (i.e. immediately after exercise and after 5 minute of exercise), significant improvement (p value <0.05) in working memory was seen as compared to the baseline resting session while no such significant beneficial improvement was seen when compared between immediately after exercise and after 5 minute of exercise.Conclusion: Improvement in working memory after moderate exercise intervention was seen, which is important for learning and memory and decision-making. BJHS 2018;3(2)6:484-487.

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

British Journal Of Nutrition ◽

10.1017/s000711451500046x ◽

2015 ◽

Vol 113 (7) ◽

pp. 1170-1177 ◽

Cited By ~ 8

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.

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Diurnal variation in excitation-contraction coupling is lost in the adult spontaneously hypertensive rat heart

Journal of Hypertension ◽

10.1097/hjh.0b013e328360ae4b ◽

2013 ◽

Vol 31 (6) ◽

pp. 1214-1223 ◽

Cited By ~ 8

Author(s):

Helen E. Collins ◽

Helen E. Turrell ◽

Nilesh J. Samani ◽

Glenn C. Rodrigo

Keyword(s):

Diurnal Variation ◽

Rat Heart ◽

Spontaneously Hypertensive Rat ◽

Excitation Contraction Coupling ◽

Spontaneously Hypertensive ◽

Contraction Coupling ◽

Hypertensive Rat

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The role of voltage-gated Na+ channels in excitation–contraction coupling of rat heart determined by BmK I, an α-like scorpion neurotoxin

Toxicology in Vitro ◽

10.1016/j.tiv.2004.07.005 ◽

2005 ◽

Vol 19 (2) ◽

pp. 183-190 ◽

Cited By ~ 7

Author(s):

Hai-Ying Sun ◽

Zhao-Nian Zhou ◽

Yong-Hua Ji

Keyword(s):

Rat Heart ◽

Na Channels ◽

Excitation Contraction Coupling ◽

Voltage Gated ◽

Contraction Coupling ◽

Scorpion Neurotoxin ◽

Bmk I

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Excitation-contraction coupling of the developing rat heart

Biochemical Regulation of Myocardium ◽

10.1007/978-1-4613-1289-5_1 ◽

1996 ◽

pp. 5-11

Author(s):

Matti Vornanen

Keyword(s):

Rat Heart ◽

Excitation Contraction Coupling ◽

Contraction Coupling ◽

Developing Rat

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Acute Exercise Effects on Craving and Withdrawal Symptoms among Women Attempting to Quit Smoking Using Nicotine Replacement Therapy

The Journal of Smoking Cessation ◽

10.1017/jsc.2012.15 ◽

2012 ◽

Vol 7 (2) ◽

pp. 72-79 ◽

Cited By ~ 7

Author(s):

Therese Harper ◽

Lyndsay Fitzgeorge ◽

Amelia Tritter ◽

Harry Prapavessis

Keyword(s):

Smoking Cessation ◽

Replacement Therapy ◽

Nicotine Replacement Therapy ◽

Acute Exercise ◽

Physical Symptoms ◽

Withdrawal Symptoms ◽

Moderate Intensity ◽

Exercise Session ◽

Nicotine Replacement ◽

Quit Smoking

Background: Cigarette cravings are one of the most often expressed difficulties related to quitting. The effect of acute exercise on craving and withdrawal symptoms during a pharmacological based smoking cessation intervention is unknown. Methods: Participants included female smokers (n = 178) undertaking the Getting Physical on Cigarettes trial — a 14-week exercise-aided nicotine replacement therapy (NRT, i.e. patch) cessation program. They completed the Shiffman-Jarvik scale immediately before and after the first scheduled exercise session during weeks 5, 11, and 13. The first exercise session (week 5) occurred shortly after participants quit smoking (week 4) and began their 21 mg NRT patch dose. The second and third exercise bout coincided soon after participants stepped down their NRT strength to 14 mg (week 11) and 7 mg (week 13), respectively. Results: Significant reductions in cigarette craving were demonstrated following exercise at all three time points (i.e. week 5, 11, and 13). Significant reductions in psychological and sedation withdrawal symptoms were shown at week 5 and 11, but not at week 13. Significant increases in physical symptoms were found at week 5 and 11, but not week 13. No significant change in appetite was evident at any time point. Conclusions: An acute bout of moderate intensity exercise can alleviate cravings as well as psychological and sedation withdrawal symptoms in quitters during a 14-week exercise-aided NRT smoking cessation program. Promoting exercise among women using NRT is recommended.

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