Eicosanoid Production following One Bout of Exercise in Middle-Aged African American Pre- and Stage 1 Hypertensives

Endothelial dysfunction and a sedentary lifestyle may be involved in the development of hypertension which is proliferative among middle-aged African Americans (AA). Signaling molecules derived from the oxidation of 20-carbon fatty acid molecules known as eicosanoids influence vascular tone. The relationship between aerobic fitness and eicosanoid formation following exercise in middle-aged African American hypertensives is unknown.Purpose. To determine the relationship between aerobic capacity and eicosanoid formation after a bout of moderate-intensity exercise in middle-aged AA hypertensives.Methods. Ten sedentary hypertensive AA underwent 50 min of aerobic exercise at 65% VO2max. Urine was collected for 24 hr on two occasions, prior to testing and immediately following the bout of exercise. Urinary metabolites of prostacyclin (6-keto PGF1α) and thromboxane (11-dTXB2) were measured during the day and night periods by high-performance liquid chromatography (HPLC).Results. 6-keto PGF1αlevels significantly increased () following the bout of exercise compared to the control day. There was a significant relationship (, ) between 6-keto PGF1αlevels and VO2max during the exercise day.Conclusion. Based on this preliminary study, there appears to be a relationship between aerobic capacity and exercise-induced 6-keto PGF1αproduction in middle-aged hypertensive AAs. AAs with lower VO2max had lower 6-keto PGF1αformation.

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Hippocampal Blood Flow Is Increased After 20 min of Moderate-Intensity Exercise

Cerebral Cortex ◽

10.1093/cercor/bhz104 ◽

2019 ◽

Vol 30 (2) ◽

pp. 525-533 ◽

Cited By ~ 4

Author(s):

J J Steventon ◽

C Foster ◽

H Furby ◽

D Helme ◽

R G Wise ◽

...

Keyword(s):

Blood Flow ◽

Temporal Dynamics ◽

Therapeutic Potential ◽

Cerebrovascular Reactivity ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Exercise Interventions ◽

Before And After ◽

Exercise Induced

Abstract Long-term exercise interventions have been shown to be a potent trigger for both neurogenesis and vascular plasticity. However, little is known about the underlying temporal dynamics and specifically when exercise-induced vascular adaptations first occur, which is vital for therapeutic applications. In this study, we investigated whether a single session of moderate-intensity exercise was sufficient to induce changes in the cerebral vasculature. We employed arterial spin labeling magnetic resonance imaging to measure global and regional cerebral blood flow (CBF) before and after 20 min of cycling. The blood vessels’ ability to dilate, measured by cerebrovascular reactivity (CVR) to CO2 inhalation, was measured at baseline and 25-min postexercise. Our data showed that CBF was selectively increased by 10–12% in the hippocampus 15, 40, and 60 min after exercise cessation, whereas CVR to CO2 was unchanged in all regions. The absence of a corresponding change in hippocampal CVR suggests that the immediate and transient hippocampal adaptations observed after exercise are not driven by a mechanical vascular change and more likely represents an adaptive metabolic change, providing a framework for exploring the therapeutic potential of exercise-induced plasticity (neural, vascular, or both) in clinical and aged populations.

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The effect of breaking up prolonged sitting on paired associative stimulation-induced plasticity

Experimental Brain Research ◽

10.1007/s00221-020-05866-z ◽

2020 ◽

Vol 238 (11) ◽

pp. 2497-2506 ◽

Cited By ~ 1

Author(s):

E. Bojsen-Møller ◽

M. M. Ekblom ◽

O. Tarassova ◽

D. W. Dunstan ◽

O. Ekblom

Keyword(s):

Physical Activity ◽

Motor Cortex ◽

Fixed Effects ◽

Primary Motor Cortex ◽

Short Interval ◽

Moderate Intensity ◽

Middle Aged ◽

Moderate Intensity Exercise ◽

Abductor Pollicis Brevis ◽

Paired Associative Stimulation

Abstract Paired associative stimulation (PAS) can induce plasticity in the motor cortex, as measured by changes in corticospinal excitability (CSE). This effect is attenuated in older and less active individuals. Although a single bout of exercise enhances PAS-induced plasticity in young, physically inactive adults, it is not yet known if physical activity interventions affect PAS-induced neuroplasticity in middle-aged inactive individuals. Sixteen inactive middle-aged office workers participated in a randomized cross-over design investigating how CSE and short-interval intracortical inhibition (SICI) were affected by PAS preceded by 3 h of sitting (SIT), 3 h of sitting interrupted every 30 min by 3 min of frequent short bouts of physical activity (FPA) and 2.5 h of sitting followed by 25 min of moderate-intensity exercise (EXE). Transcranial magnetic stimulation was applied over the primary motor cortex (M1) of the dominant abductor pollicis brevis to induce recruitment curves before and 5 min and 30 min post-PAS. Linear mixed models were used to compare changes in CSE using time and condition as fixed effects and subjects as random effects. There was a main effect of time on CSE and planned within-condition comparisons showed that CSE was significantly increased from baseline to 5 min and 30 min post-PAS, in the FPA condition, with no significant changes in the SIT or EXE conditions. SICI decreased from baseline to 5 min post-PAS, but this was not related to changes in CSE. Our findings suggest that in middle-aged inactive adults, FPAs may promote corticospinal neuroplasticity. Possible mechanisms are discussed.

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Impact of cocoa flavanol consumption on blood pressure responsiveness to exercise

British Journal Of Nutrition ◽

10.1017/s0007114509993382 ◽

2010 ◽

Vol 103 (10) ◽

pp. 1480-1484 ◽

Cited By ~ 55

Author(s):

Narelle M. Berry ◽

Kade Davison ◽

Alison M. Coates ◽

Jonathan D. Buckley ◽

Peter R. C. Howe

Keyword(s):

Blood Pressure ◽

Analysis Of Covariance ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Double Blind ◽

Flow Mediated Dilatation ◽

Dependent Flow ◽

Exercise Induced ◽

Response To Exercise ◽

Cocoa Flavanols

Impaired endothelial vasodilatation may contribute to the exaggerated blood pressure (BP) responses to exercise in individuals who are overweight/obese. The present study investigated whether consumption of cocoa flavanols, which improve endothelium-dependent flow-mediated dilatation (FMD), can modify BP responsiveness to exercise. Twenty-one volunteers (eight females and thirteen males, 54·9 (se2·2) years, BMI 31·6 (se0·8) kg/m2, systolic BP 134 (se2) mmHg, diastolic BP (DBP) 87 (se2) mmHg) were randomised to consume single servings of either a high-flavanol (HF, 701 mg) or a low-flavanol (LF, 22 mg) cocoa beverage in a double-blind, cross-over design with 3–7-d washout between treatments. Two hours after cocoa consumption, FMD was measured, followed by continuous beat-to-beat assessment (Finapres™) of BP before and during 10 min of cycling at 75 % of age-predicted maximum heart rate. Averaged data from two assessments on each type of beverage were compared by analysis of covariance using pre-exercise BP as the covariate. Pre-exercise BP was similar after taking LF and HF (153 (se3)/88 (se3)v. 153 (se4)/87 (se2) mmHg, respectively,P>0·05). However, the BP response to exercise (area under BP curve) was attenuated by HF compared with LF. BP increases were 68 % lower for DBP (P = 0·03) and 14 % lower for mean BP (P = 0·05). FMD measurements were higher after taking HF than after taking LF (6·1 (se0·6) %v. 3·4 (se0·5) %,P < 0·001). By facilitating vasodilation and attenuating exercise-induced increases in BP, cocoa flavanols may decrease cardiovascular risk and enhance the cardiovascular benefits of moderate intensity exercise in at-risk individuals.

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O2 uptake kinetics, pyruvate dehydrogenase activity, and muscle deoxygenation in young and older adults during the transition to moderate-intensity exercise

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00537.2007 ◽

2008 ◽

Vol 294 (2) ◽

pp. R577-R584 ◽

Cited By ~ 36

Author(s):

B. J. Gurd ◽

S. J. Peters ◽

G. J. F. Heigenhauser ◽

P. J. LeBlanc ◽

T. J. Doherty ◽

...

Keyword(s):

Older Adults ◽

Young Adults ◽

Pyruvate Dehydrogenase ◽

Lactate Threshold ◽

Time Course ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Similar Time ◽

O2 Uptake Kinetics ◽

The Relationship

The adaptation of pulmonary O2 uptake (V̇o2p) kinetics is slowed in older compared with young adults during the transition to moderate-intensity exercise. In this study, we examined the relationship between V̇o2p kinetics and mitochondrial pyruvate dehydrogenase (PDH) activity in young ( n = 7) and older ( n = 6) adults. Subjects performed cycle exercise to a work rate corresponding to ∼90% of estimated lactate threshold. Phase 2 V̇o2p kinetics were slower ( P < 0.05) in older (τ = 40 ± 17 s) compared with young (τ = 21 ± 6 s) adults. Relative phosphocreatine (PCr) breakdown was greater ( P < 0.05) at 30 s in older compared with young adults. Absolute PCr breakdown at 6 min was greater ( P < 0.05) in older compared with young adults. In young adults, PDH activity increased ( P < 0.05) from baseline to 30 s, with no further change observed at 6 min. In older adults, PDH activity during baseline exercise was similar to that seen in young adults. During the exercise transition, PDH activity did not increase ( P > 0.05) at 30 s of exercise but was elevated ( P < 0.05) after 6 min. The change in deoxyhemoglobin (HHb) was greater for a given V̇o2p in older adults, and there was a similar time course of HHb accompanying the slower V̇o2p kinetics in the older adults, suggesting a slower adaptation of bulk O2 delivery in older adults. In conclusion, the slower adaptation of V̇o2p in older adults is likely a result of both an increased metabolic inertia and lower O2 availability.

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Physical Activity, Exercise, and the Immune System: Three Lines of Research That Have Driven the Field

Kinesiology Review ◽

10.1123/kr.2014-0086 ◽

2015 ◽

Vol 4 (1) ◽

pp. 118-125

Author(s):

Jeffrey A. Woods ◽

Brandt D. Pence

Keyword(s):

Immune System ◽

Immune Function ◽

Acute Exercise ◽

Prolonged Exercise ◽

Moderate Intensity ◽

Upper Respiratory Tract ◽

Moderate Intensity Exercise ◽

Exercise Immunology ◽

Upper Respiratory ◽

Exercise Induced

Exercise immunology is a relatively new discipline in the exercise sciences that seeks to understand how exercise affects the immune system and susceptibility to infectious and chronic diseases. This brief review will focus on three major observations that have driven the field to date including: (1) acute exercise-induced leukocytosis, (2) the observation that intense, prolonged exercise results in upper respiratory tract symptoms, and (3) the paradoxical effect of acute and chronic exercise on inflammation. This framework will be used to examine the mechanisms and implications behind these seminal observations. Data generally support the conclusion that moderate intensity exercise enhances immune function, whereas prolonged, intense exercise diminishes immune function.

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Human lung density is not altered following normoxic and hypoxic moderate-intensity exercise: implications for transient edema

Journal of Applied Physiology ◽

10.1152/japplphysiol.01087.2006 ◽

2007 ◽

Vol 103 (1) ◽

pp. 111-118 ◽

Cited By ~ 22

Author(s):

Alastair N. H. Hodges ◽

A. William Sheel ◽

John R. Mayo ◽

Donald C. McKenzie

Keyword(s):

Arterial Oxygen Saturation ◽

Moderate Intensity ◽

Arterial Oxygen ◽

Moderate Intensity Exercise ◽

Lung Water ◽

Lung Density ◽

Cycling Exercise ◽

Pulmonary Capillary ◽

Interstitial Pulmonary Edema ◽

Exercise Induced

The purpose of this study was to examine the effects of exercise on extravascular lung water as it may relate to pulmonary gas exchange. Ten male humans underwent measures of maximal oxygen uptake (V̇o2 max) in two conditions: normoxia (N) and normobaric hypoxia of 15% O2 (H). Lung density was measured by quantified MRI before and 48.0 ± 7.4 and 100.7 ± 15.1 min following 60 min of cycling exercise in N (intensity = 61.6 ± 9.5% V̇o2 max) and 55.5 ± 9.8 and 104.3 ± 9.1 min following 60 min cycling exercise in H (intensity = 65.4 ± 7.1% hypoxic V̇o2 max), where V̇o2 max = 65.0 ± 7.5 ml·kg−1·min−1 (N) and 54.1 ± 7.0 ml·kg−1·min−1 (H). Two subjects demonstrated mild exercise-induced arterial hypoxemia (EIAH) [minimum arterial oxygen saturation (SaO2 min) = 94.5% and 93.8%], and seven subjects demonstrated moderate EIAH (SaO2 min = 91.4 ± 1.1%) as measured noninvasively during the V̇o2 max test in N. Mean lung densities, measured once preexercise and twice postexercise, were 0.177 ± 0.019, 0.181 ± 0.019, and 0.173 ± 0.019 g/ml (N) and 0.178 ± 0.021, 0.174 ± 0.022, and 0.176 ± 0.019 g/ml (H), respectively. No significant differences ( P > 0.05) were found in lung density following exercise in either condition or between conditions. Transient interstitial pulmonary edema did not occur following sustained steady-state cycling exercise in N or H, indicating that transient edema does not result from pulmonary capillary leakage during sustained submaximal exercise.

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Red Blood Cell Aging as a Homeostatic Response to Exercise-Induced Stress

Applied Sciences ◽

10.3390/app9224827 ◽

2019 ◽

Vol 9 (22) ◽

pp. 4827 ◽

Cited By ~ 1

Author(s):

Joames K. Freitas Leal ◽

Dan Lazari ◽

Coen C.W.G. Bongers ◽

Maria T.E. Hopman ◽

Roland Brock ◽

...

Keyword(s):

Blood Cell ◽

Red Blood Cells ◽

Red Blood Cell ◽

Blood Cells ◽

Molecular Mechanisms ◽

Moderate Intensity ◽

Cell Aging ◽

Moderate Intensity Exercise ◽

Induced Stress ◽

Exercise Induced

Our knowledge on the molecular mechanisms of red blood cell aging is mostly derived from in vitro studies. The Four Days Marches of Nijmegen in the Netherlands, the world’s largest yearly walking event, constitutes a unique possibility to study the effect of mechanical and biochemical stressors occurring during moderate-intensity exercise on red blood cell aging in vivo. Therefore, longitudinal measurements were performed of biophysical, immunological, and functional red blood cell characteristics that are known to change during aging. Our data show that moderate-intensity exercise induces the generation of a functionally improved red blood cell population with a higher deformability and a decreased tendency to aggregate. This is likely to be associated with an early removal of the oldest red blood cells from the circulation, as deduced from the (dis)appearance of removal signals. Thus, the physiological red blood cell aging process maintains homeostasis in times of moderate-intensity exercise-induced stress, probably by accelerated aging and subsequent removal of the oldest, most vulnerable red blood cells.

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Effects of Acute Exercise on Memory Performance in Middle-Aged and Older Adults

Journal of Aging and Physical Activity ◽

10.1123/japa.2020-0208 ◽

2020 ◽

pp. 1-8

Author(s):

Jennifer L. Etnier ◽

Jarod C. Vance ◽

Aiko Ueno

Keyword(s):

Older Adults ◽

Acute Exercise ◽

Memory Performance ◽

Moderate Intensity ◽

Long Term Memory ◽

Middle Aged ◽

Moderate Intensity Exercise ◽

Auditory Learning ◽

Verbal Test ◽

Within Subjects

Numerous studies show that exercise benefits memory and some show that acute exercise prior to encoding has larger benefits than exercise after encoding. This study was designed to investigate the effects of acute exercise on memory in middle-aged and older adults (Mage = 64.71 years) and to explore the influence of the timing of the exercise on these effects. Using a within-subjects design, moderate-intensity exercise (20 min) was either not performed (control), performed before the task (exercise prior), or performed after the task (exercise post). Memory was assessed using the Rey Auditory Learning Verbal Test. For short- and long-term memory and learning, significantly more words were remembered in the exercise-prior condition than the others. For 24-hr recall, participants remembered significantly more words in the exercise-prior condition than exercise post, which was better than control. Exercise benefits memory for healthy middle-aged and older adults, with the greatest benefits when performed prior to encoding.

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