Effect of Moderate Intensity Exercise Dose on Lipoprotein Concentrations and Particle Size in Older Women

This study is the first to describe, graphically and quantitatively, critical environmental limits for women between the ages of 62 and 80 yr based on the biophysics of heat exchange. These psychrometric limit lines define combinations of ambient temperature and humidity above which human heat balance cannot be maintained for a given metabolic heat production. These limits, and associated critical evaporative coefficients ( Ke′), can be used to model low- to moderate-intensity exercise responses in hot environments and have directly translatable data that can be used for evidence-based policy decisions, to prepare for impending heat events, and for implementation of other safety interventions.

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Oxygen uptake kinetics in endurance-trained and untrained postmenopausal women

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2012-0173 ◽

2013 ◽

Vol 38 (2) ◽

pp. 154-160 ◽

Cited By ~ 9

Author(s):

Shilpa Dogra ◽

Matthew D. Spencer ◽

Juan M. Murias ◽

Donald H. Paterson

Keyword(s):

Heart Rate ◽

Oxygen Uptake ◽

Older Women ◽

Near Infrared ◽

Ventilatory Threshold ◽

Vastus Lateralis ◽

Hemoglobin Concentration ◽

Oxygen Uptake Kinetics ◽

Moderate Intensity ◽

Moderate Intensity Exercise

The rate of adjustment for pulmonary oxygen uptake (τV̇O2p) is slower in untrained and in older adults. Near-infrared spectroscopy (NIRS) has shed light on potential mechanisms underlying this in young men and women and in older men; however, there is no such data available in older women. The purpose of this study was to gain a better understanding of the mechanisms of slower τV̇O2p in older women who were either endurance-trained or untrained. Endurance-trained (n = 10; age, 62.6 ± 1.0 years) and untrained (n = 9; age, 69.1 ± 2.2 years) older women attended 2 maximal and 2 submaximal (90% of ventilatory threshold) exercise sessions. Oxygen uptake (V̇O2) was measured breath by breath, using a mass spectrometer, and changes in deoxygenated hemoglobin concentration of the vastus lateralis ([HHb]) were measured using NIRS. Heart rate was measured continuously with a 3-lead electrocardiogram. τV̇O2p was faster in trained (35.1 ± 5.5 s) than in untrained (57.0 ± 8.1 s) women. The normalized [HHb] to V̇O2 ratio, an indicator of muscle O2 delivery to O2 utilization, indicated a smaller overshoot in trained (1.09 ± 0.1) than in untrained (1.39 ± 0.1) women. Heart rate data indicated a faster adjustment of heart rate in trained (33.0 ± 13.0) than in untrained (68.7 ± 14.1) women. The pairing of V̇O2p data with NIRS-derived [HHb] data indicates that endurance-trained older women likely have better matching of O2 delivery to O2 utilization than older untrained women during moderate-intensity exercise, leading to a more rapid adjustment of V̇O2p.

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Effect of age on heat-activated sweat gland density and flow during exercise in dry heat

Journal of Applied Physiology ◽

10.1152/jappl.1987.63.3.1089 ◽

1987 ◽

Vol 63 (3) ◽

pp. 1089-1094 ◽

Cited By ~ 66

Author(s):

R. K. Anderson ◽

W. L. Kenney

Keyword(s):

Older Women ◽

Sweat Gland ◽

Age Groups ◽

Whole Body ◽

Moderate Intensity ◽

Exercise Session ◽

Sweat Glands ◽

Moderate Intensity Exercise ◽

Age Related ◽

Eccrine Glands

Physiological responses of eight postmenopausal older women (age 52–62 yr) and eight younger women (age 20–30 yr) were compared during moderate intensity exercise in a hot dry environment (48 degrees C dry bulb, 25 degrees C wet bulb). The age groups were matched on the basis of maximal O2 consumption (VO2max), body surface area, and body fatness. After heat acclimation the women walked at 40% VO2max for up to 2 h in the hot dry environment while heart rate (HR), rectal temperature (Tre), mean skin temperature (Tsk), whole-body sweating rate (Msw), and local sweating rates (msw; forearm, chest, and scapula) were measured. Additionally, the density of heat-activated sweat glands (HASG) was determined and average sweat gland flow (SGF) was calculated for the scapular area. Although no differences between age groups were found in HR response (when analyzed as percent of maximal HR) or Tsk, the older women had a significantly higher Tre throughout the heat-exercise session. The greater heat storage of the older women may be explained by their significantly lower Msw and msw. There were no differences between the younger and older women in the density of HASG after 30 min; therefore, the lower msw reflects a diminished output per HASG rather than a decrease in the number of sweat glands recruited. The diminished thermoregulatory ability of the older women, unrelated to differences in VO2max, appears to reflect either 1) a diminished response of the sweat glands to central and/or peripheral stimuli, or 2) an age-related structural alteration in the eccrine glands or surrounding skin cells.

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A Systematic Review Comparing Dose Response of Exercise on Cardiovascular and All-Cause Mortality

Home Health Care Management & Practice ◽

10.1177/1084822319831929 ◽

2019 ◽

Vol 31 (4) ◽

pp. 263-273

Author(s):

Elizabeth Moxley ◽

Desale Habtzghi

Keyword(s):

Dose Response ◽

Cardiovascular Mortality ◽

Low Dose ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Vigorous Exercise ◽

Physical Activity Guidelines ◽

All Cause Mortality ◽

Vigorous Intensity ◽

Exercise Dose

It is well established that exercise improves cardiovascular and all-cause mortality, although an ideal dose of exercise is not known. The physical activity guidelines currently recommend 150 minutes per week of moderate-intensity exercise or 75 minutes of vigorous-intensity activity. Most individuals do not engage in adequate exercise, although a safe upper limit does not exist and a too much exercise hypothesis has recently emerged. This review of the literature analyzes studies that have evaluated exercise dose response on all-cause and cardiovascular mortality for the purpose of determining safe and effective exercise prescriptions. Searches were performed in PubMed and CINAHL between 2010 and 2018 to identify six studies that met inclusion criteria. Moderate-intensity exercise reduced all-cause mortality in five of six studies, whereas low-dose exercise most effectively improved all-cause mortality in three studies, and cardiovascular mortality in one study. Vigorous-intensity exercise or extreme doses demonstrated variable outcomes and remain controversial; two studies found vigorous-intensity exercise beneficial to improve health, two studies discouraged vigorous exercise, and two studies had less conclusive outcomes. It is not surprising that any amount of exercise improves health compared with none at all, with the greatest benefits observed when sedentary individuals began exercising. Low-dose exercise should be recommended to everyone with a goal of meeting the minimal requirements according to guidelines for decreased all-cause and cardiovascular mortality. Additional research to more thoroughly understand exercise dose response and motivate individuals to improve exercise engagement is currently warranted.

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Effect of healthy aging and sex on middle cerebral artery blood velocity dynamics during moderate-intensity exercise

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00129.2018 ◽

2018 ◽

Vol 315 (3) ◽

pp. H492-H501 ◽

Cited By ~ 13

Author(s):

Jaimie L. Ward ◽

Jesse C. Craig ◽

Yumei Liu ◽

Eric D. Vidoni ◽

Rebecca Maletsky ◽

...

Keyword(s):

Middle Cerebral Artery ◽

Older Women ◽

Cerebral Artery ◽

Blood Velocity ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Cerebrovascular Function ◽

Age Related ◽

Young Subjects ◽

Response To Exercise

Blood velocity measured in the middle cerebral artery (MCAV) increases with finite kinetics during moderate-intensity exercise, and the amplitude and dynamics of the response provide invaluable insights into the controlling mechanisms. The MCAV response after exercise onset is well fit to an exponential model in young individuals but remains to be characterized in their older counterparts. The responsiveness of vasomotor control degrades with advancing age, especially in skeletal muscle. We tested the hypothesis that older subjects would evince a slower and reduced MCAV response to exercise. Twenty-nine healthy young (25 ± 1 yr old) and older (69 ± 1 yr old) adults each performed a rapid transition from rest to moderate-intensity exercise on a recumbent stepper. Resting MCAV was lower in older than young subjects (47 ± 2 vs. 64 ± 3 cm/s, P < 0.001), and amplitude from rest to steady-state exercise was lower in older than young subjects (12 ± 2 vs. 18 ± 3 cm/s, P = 0.04), even after subjects were matched for work rate. As hypothesized, the time constant was significantly longer (slower) in the older than young subjects (51 ± 10 vs. 31 ± 4 s, P = 0.03), driven primarily by older women. Neither age-related differences in fitness, end-tidal CO2, nor blood pressure could account for this effect. Thus, MCAV kinetic analyses revealed a marked impairment in the cerebrovascular response to exercise in older individuals. Kinetic analysis offers a novel approach to evaluate the efficacy of therapeutic interventions for improving cerebrovascular function in elderly and patient populations. NEW & NOTEWORTHY Understanding the dynamic cerebrovascular response to exercise has provided insights into sex-related cerebrovascular control mechanisms throughout the aging process. We report novel differences in the kinetics response of cerebrovascular blood velocity after the onset of moderate-intensity exercise. The exponential increase in brain blood flow from rest to exercise revealed that 1) the kinetics profile of the older group was blunted compared with their young counterparts and 2) the older women demonstrated a slowed response.

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Moderate and heavy oxygen uptake kinetics in postmenopausal women

Applied Physiology Nutrition and Metabolism ◽

10.1139/h09-107 ◽

2009 ◽

Vol 34 (6) ◽

pp. 1065-1072 ◽

Cited By ~ 3

Author(s):

Liza Stathokostas ◽

John M. Kowalchuk ◽

Robert J. Petrella ◽

Donald H. Paterson

Keyword(s):

Oxygen Uptake ◽

Postmenopausal Women ◽

Older Women ◽

Ventilatory Threshold ◽

Hormone Replacement ◽

Oxygen Uptake Kinetics ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Repeated Exercise ◽

Exercise Transitions

The lack of estrogen in postmenopausal women not using hormone replacement therapy (HRT), compared with those using HRT, may reduce submaximal blood flow during exercise and result in an oxygen delivery limitation constraining oxygen uptake (VO2) kinetics. The adaptation of pulmonary VO2 (VO2p) during the transition to exercise in older women was examined in this study. Thirty-one healthy postmenopausal women (mean age, 61 ± 6 years), 15 not using HRT and 16 using HRT, performed repeated exercise transitions (6 min) on a cycle, to work rates corresponding to 80% of estimated ventilatory threshold (moderate-intensity exercise) and to Δ50 (heavy-intensity exercise). There was no difference in moderate-intensity τVO2p between non-HRT (40 ± 9 s) and HRT (41 ± 9 s) women. Similarly, there was no difference in heavy-intensity τVO2p between non-HRT (44 ± 8 s) and HRT (45 ± 8 s) women. Thus, HRT did not affect the slowing of VO2 kinetics of older women.

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The effect of moderate-intensity exercise on nightly variability in objectively measured sleep parameters among older women

Behavioral Sleep Medicine ◽

10.1080/15402002.2017.1395337 ◽

2017 ◽

Vol 17 (4) ◽

pp. 459-469 ◽

Cited By ~ 3

Author(s):

Charity B. Breneman ◽

Christopher E. Kline ◽

Delia S. West ◽

Xuemei Sui ◽

Ryan R. Porter ◽

...

Keyword(s):

Older Women ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Sleep Parameters ◽

Objectively Measured

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A moderate intensity exercise program improves physical function and oxidative damage in older women with and without sarcopenic obesity

Experimental Gerontology ◽

10.1016/j.exger.2021.111360 ◽

2021 ◽

pp. 111360

Author(s):

Liliana Gutiérrez-López ◽

Ivonne M. Olivares-Corichi ◽

Liliam Y. Martínez-Arellanes ◽

Eduardo Mejía-Muñoz ◽

José A. Polanco-Fierro ◽

...

Keyword(s):

Oxidative Damage ◽

Physical Function ◽

Older Women ◽

Exercise Program ◽

Sarcopenic Obesity ◽

Moderate Intensity ◽

Moderate Intensity Exercise

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Acute and Chronic Effects of Low-Volume High-Intensity Interval Training Compared to Moderate-Intensity Continuous Training on Glycemic Control and Body Composition in Older Women with Type 2 Diabetes

Obesities ◽

10.3390/obesities1020007 ◽

2021 ◽

Vol 1 (2) ◽

pp. 72-87

Author(s):

Alexis Marcotte-Chénard ◽

Dominic Tremblay ◽

Marie-Michelle Mony ◽

Pierre Boulay ◽

Martin Brochu ◽

...

Keyword(s):

Body Composition ◽

Older Women ◽

Interval Training ◽

Moderate Intensity ◽

Continuous Training ◽

Glucose Levels ◽

Mild Hyperglycemia ◽

Low Volume ◽

High Intensity Interval

Objective: To compare the acute and chronic effects of low-volume high-intensity interval training (HIIT) to moderate-intensity continuous training (MICT) on glycemic control, body composition and continuous glucose monitoring (CGM) in older women with type 2 diabetes (T2D). Methods: Thirty older women (68 ± 5 years) with T2D were randomized in two groups—HIIT (75 min/week) or MICT (150 min/week). Glucose homeostasis (A1c, glucose, insulin, HOMA-IR2) and body composition (iDXA) were measured before and after the 12-week exercise intervention. During the first and last week of training (24-h before and 48-h after exercise), the following CGM-derived data were measured: 24-h and peak glucose levels, glucose variability and time spent in hypoglycemia as well as severe and mild hyperglycemia. Results: While lean body mass increased (p = 0.035), total and trunk fat mass decreased (p ≤ 0.007), without any difference between groups (p ≥ 0.81). Fasting glucose levels (p = 0.001) and A1c (p = 0.014) significantly improved in MICT only, with a significant difference between groups for fasting glucose (p = 0.02). Neither HIIT nor MICT impacted CGM-derived data at week 1 (p ≥ 0.25). However, 24-h and peak glucose levels, as well as time spent in mild hyperglycemia, decreased in HIIT at week 12 (p ≤ 0.03). Conclusion: These results suggest that 12 weeks of low-volume HIIT is enough to provide similar benefit to MICT for body composition and improve the acute effect of exercise when measured with CGM.

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Hypertrophic Cardiomyopathy: Updates Through the Lens of Sports Cardiology

Current Treatment Options in Cardiovascular Medicine ◽

10.1007/s11936-021-00934-1 ◽

2021 ◽

Vol 23 (8) ◽

Author(s):

Bradley S. Lander ◽

Dermot M. Phelan ◽

Matthew W. Martinez ◽

Elizabeth H. Dineen

Keyword(s):

Decision Making ◽

Hypertrophic Cardiomyopathy ◽

Shared Decision Making ◽

Sport Participation ◽

Heart Association ◽

Moderate Intensity ◽

Implantable Cardioverter Defibrillators ◽

Shared Decision ◽

Moderate Intensity Exercise ◽

Sports Cardiology

Abstract Purpose of review This review will summarize the distinction between hypertrophic cardiomyopathy (HCM) and exercise-induced cardiac remodeling (EICR), describe treatments of particular relevance to athletes with HCM, and highlight the evolution of recommendations for exercise and competitive sport participation relevant to individuals with HCM. Recent findings Whereas prior guidelines have excluded individuals with HCM from more than mild-intensity exercise, recent data show that moderate-intensity exercise improves functional capacity and indices of cardiac function and continuation of competitive sports may not be associated with worse outcomes. Moreover, recent studies of athletes with implantable cardioverter defibrillators (ICDs) demonstrated a safer profile than previously understood. In this context, the updated American Heart Association/American College of Cardiology (AHA/ACC) and European Society of Cardiology (ESC) HCM guidelines have increased focus on shared decision-making and liberalized restrictions on exercise and sport participation among individuals with HCM. Summary New data demonstrating the safety of exercise in individuals with HCM and in athletes with ICDs, in addition to a focus on shared decision-making, have led to the most updated guidelines easing restrictions on exercise and competitive athletics in this population. Further athlete-specific studies of HCM, especially in the context of emerging therapies such as mavacamten, are important to inform accurate risk stratification and eligibility recommendations.

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