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Andrade A, D’Oliveira A, De Souza LC, Bastos ACRDF, Dominski FH, Stabile L, Buonanno G. Effects of Air Pollution on the Health of Older Adults during Physical Activities: Mapping Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3506. [PMID: 36834200 PMCID: PMC9960154 DOI: 10.3390/ijerph20043506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/12/2023] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
Atmospheric pollutants present environmental threats to health and have been investigated in different environments, such as highways, squares, parks, and gyms. These environments are frequented by older adults, who are considered fragile to the harmful impacts of pollution present in the air. The aim was to analyze the state of the art on the effects of air pollution on the health of older adults during physical activities (PAs) through a mapping review. The search was performed in PubMed, Web of Science, Scopus, and Cinahl databases until June 2022. Of the 10,109 studies initially identified, 58 met the inclusion criteria. The most investigated health outcome was cardiovascular disease, followed by respiratory outcomes. Particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2), and ozone (O3) were the most investigated pollutants. Of the 75 health outcomes investigated, in 29, air pollution had harmful effects on the health of the older adults during the practice of PA, more frequently in cardiovascular diseases. In 25 outcomes, the beneficial effects of PA to the health of the older adults remained, despite exposure to high and low concentrations of pollutants, most often in terms of mental disorders. We conclude that poor air quality is a harmful factor for the health of older adults during the practice of PAs, more frequently in cardiovascular and respiratory diseases. On the other hand, for mental-health-related outcomes (depression and cognition), in most studies, the beneficial effects of PA in older adults were maintained, even after exposure to pollutants.
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Affiliation(s)
- Alexandro Andrade
- Health and Sports Science Center, Department of Physical Education, CEFID, Santa Catarina State University, Florianópolis 88035-901, Brazil
| | - Anderson D’Oliveira
- Health and Sports Science Center, Department of Physical Education, CEFID, Santa Catarina State University, Florianópolis 88035-901, Brazil
| | - Loiane Cristina De Souza
- Health and Sports Science Center, Department of Physical Education, CEFID, Santa Catarina State University, Florianópolis 88035-901, Brazil
| | | | - Fábio Hech Dominski
- Department of Physical Education, Univille University, Joinville 89219-710, Brazil
| | - Luca Stabile
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043 Cassino, Italy
| | - Giorgio Buonanno
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043 Cassino, Italy
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane 4001, Australia
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Lifelong Endurance Exercise as a Countermeasure Against Age-Related [Formula: see text] Decline: Physiological Overview and Insights from Masters Athletes. Sports Med 2021; 50:703-716. [PMID: 31873927 DOI: 10.1007/s40279-019-01252-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Maximum oxygen consumption ([Formula: see text]) is not only an indicator of endurance performance, but also a strong predictor of cardiovascular disease and mortality. This physiological parameter is known to decrease with aging. In turn, physical exercise might attenuate the rate of aging-related decline in [Formula: see text], which in light of the global population aging is of major clinical relevance, especially at advanced ages. In this narrative review, we summarize the evidence available from masters athletes about the role of lifelong endurance exercise on aging-related [Formula: see text] decline, with examples of the highest [Formula: see text] values reported in the scientific literature for athletes across different ages (e.g., 35 ml·kg-1·min-1 in a centenarian cyclist). These data suggest that a linear decrease in [Formula: see text] might be possible if physical exercise loads are kept consistently high through the entire life span, with [Formula: see text] values remaining higher than those of the general population across all ages. We also summarize the main physiological changes that occur with inactive aging at different system levels-pulmonary and cardiovascular function, blood O2 carrying capacity, skeletal muscle capillary density and oxidative capacity-and negatively influence [Formula: see text], and review how lifelong exercise can attenuate or even prevent most-but apparently not all (e.g., maximum heart rate decline)-of them. In summary, although aging seems to be invariably associated with a progressive decline in [Formula: see text], maintaining high levels of physical exercise along the life span slows the multi-systemic deterioration that is commonly observed in inactive individuals, thereby attenuating age-related [Formula: see text] decline.
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Fukuoka Y, Iihoshi M, Nazunin JT, Abe D, Fukuba Y. Dynamic Characteristics of Ventilatory and Gas Exchange during Sinusoidal Walking in Humans. PLoS One 2017; 12:e0168517. [PMID: 28076413 PMCID: PMC5226792 DOI: 10.1371/journal.pone.0168517] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/01/2016] [Indexed: 11/28/2022] Open
Abstract
Our present study investigated whether the ventilatory and gas exchange responses show different dynamics in response to sinusoidal change in cycle work rate or walking speed even if the metabolic demand was equivalent in both types of exercise. Locomotive parameters (stride length and step frequency), breath-by-breath ventilation (V̇E) and gas exchange (CO2 output (V̇CO2) and O2 uptake (V̇O2)) responses were measured in 10 healthy young participants. The speed of the treadmill was sinusoidally changed between 3 km·h-1 and 6 km·h-1 with various periods (from 10 to 1 min). The amplitude of locomotive parameters against sinusoidal variation showed a constant gain with a small phase shift, being independent of the oscillation periods. In marked contrast, when the periods of the speed oscillations were shortened, the amplitude of V̇E decreased sharply whereas the phase shift of V̇E increased. In comparing walking and cycling at the equivalent metabolic demand, the amplitude of V̇E during sinusoidal walking (SW) was significantly greater than that during sinusoidal cycling (SC), and the phase shift became smaller. The steeper slope of linear regression for the V̇E amplitude ratio to V̇CO2 amplitude ratio was observed during SW than SC. These findings suggested that the greater amplitude and smaller phase shift of ventilatory dynamics were not equivalent between SW and SC even if the metabolic demand was equivalent between both exercises. Such phenomenon would be derived from central command in proportion to locomotor muscle recruitment (feedforward) and muscle afferent feedback.
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Affiliation(s)
- Yoshiyuki Fukuoka
- Laboratory of Environmental Physiology, Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
- Laboratory of Environmental Physiology, Faculty of Health and Sports Science, Doshisha University, Kyotanabe, Japan
- * E-mail:
| | - Masaaki Iihoshi
- Laboratory of Environmental Physiology, Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Juhelee Tuba Nazunin
- Laboratory of Environmental Physiology, Faculty of Health and Sports Science, Doshisha University, Kyotanabe, Japan
| | - Daijiro Abe
- Biodynamics Laboratory, Center for Health and Sports Science, Kyushu Sangyo University, Fukuoka, Japan
| | - Yoshiyuki Fukuba
- Department of Sports Science and Physiology, Hiroshima Prefectural University, Hiroshima, Japan
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The effect of adding CO2 to hypoxic inspired gas on cerebral blood flow velocity and breathing during incremental exercise. PLoS One 2013; 8:e81130. [PMID: 24278389 PMCID: PMC3836745 DOI: 10.1371/journal.pone.0081130] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 10/09/2013] [Indexed: 11/19/2022] Open
Abstract
Hypoxia increases the ventilatory response to exercise, which leads to hyperventilation-induced hypocapnia and subsequent reduction in cerebral blood flow (CBF). We studied the effects of adding CO2 to a hypoxic inspired gas on CBF during heavy exercise in an altitude naïve population. We hypothesized that augmented inspired CO2 and hypoxia would exert synergistic effects on increasing CBF during exercise, which would improve exercise capacity compared to hypocapnic hypoxia. We also examined the responsiveness of CO2 and O2 chemoreception on the regulation ventilation (E) during incremental exercise. We measured middle cerebral artery velocity (MCAv; index of CBF), E, end-tidal PCO2, respiratory compensation threshold (RC) and ventilatory response to exercise (E slope) in ten healthy men during incremental cycling to exhaustion in normoxia and hypoxia (FIO2 = 0.10) with and without augmenting the fraction of inspired CO2 (FICO2). During exercise in normoxia, augmenting FICO2 elevated MCAv throughout exercise and lowered both RC onset andE slope below RC (P<0.05). In hypoxia, MCAv and E slope below RC during exercise were elevated, while the onset of RC occurred at lower exercise intensity (P<0.05). Augmenting FICO2 in hypoxia increased E at RC (P<0.05) but no difference was observed in RC onset, MCAv, or E slope below RC (P>0.05). The E slope above RC was unchanged with either hypoxia or augmented FICO2 (P>0.05). We found augmenting FICO2 increased CBF during sub-maximal exercise in normoxia, but not in hypoxia, indicating that the ‘normal’ cerebrovascular response to hypercapnia is blunted during exercise in hypoxia, possibly due to an exhaustion of cerebral vasodilatory reserve. This finding may explain the lack of improvement of exercise capacity in hypoxia with augmented CO2. Our data further indicate that, during exercise below RC, chemoreception is responsive, while above RC the ventilatory response to CO2 is blunted.
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Babb TG. Obesity: challenges to ventilatory control during exercise--a brief review. Respir Physiol Neurobiol 2013; 189:364-70. [PMID: 23707540 DOI: 10.1016/j.resp.2013.05.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 05/14/2013] [Accepted: 05/15/2013] [Indexed: 10/26/2022]
Abstract
Obesity is a national health issue in the US. Among the many physiological changes induced by obesity, it also presents a unique challenge to ventilatory control during exercise due to increased metabolic demand of moving larger limbs, increased work of breathing due to extra weight on the chest wall, and changes in breathing mechanics. These challenges to ventilatory control in obesity can be inconspicuous or overt among obese adults but for the most part adaptation of ventilatory control during exercise in obesity appears remarkably unnoticed in the majority of obese people. In this brief review, the changes to ventilatory control required for maintaining normal ventilation during exercise will be examined, especially the interaction between respiratory neural drive and ventilation. Also, gaps in our current knowledge will be discussed.
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Affiliation(s)
- Tony G Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75231, United States.
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Effects of Heliox in Stable COPD Patients at Rest and during Exercise. Pulm Med 2012; 2012:593985. [PMID: 23094152 PMCID: PMC3475004 DOI: 10.1155/2012/593985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 09/14/2012] [Indexed: 11/17/2022] Open
Abstract
Heliox has been administered to stable chronic obstructive pulmonary disease (COPD) patients at rest and during exercise on the assumption that this low density mixture would have reduced work of breathing, dynamic hyperinflation, and, consequently, dyspnea sensation. Contrary to these expectations, beneficial effects of heliox in these patients at rest have been reported only sporadically, and the majority of the studies performed until now suggests that heliox is not a therapeutic option in spontaneously breathing resting COPD patients. On the other hand, when it is administered to COPD patients exercising at a constant work rate, heliox systematically decreases dyspnea sensation, and, often but not always, increases exercise tolerance. For these reasons, heliox has been evaluated as a non pharmacological tool to power rehabilitation programs. The conflicting results provided by the published trials probably point at a substantial heterogeneity of the COPD patients population in terms of respiratory mechanics and gas exchange. Therefore, further studies, aimed to the identification of mechanisms conditioning the response of exercising COPD patients to heliox, are warranted, before heliox administration, which is costly and cumbersome, can be routinely used in rehabilitation programs.
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Jensen D, Ofir D, O’Donnell DE. Effects of pregnancy, obesity and aging on the intensity of perceived breathlessness during exercise in healthy humans. Respir Physiol Neurobiol 2009; 167:87-100. [DOI: 10.1016/j.resp.2009.01.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 01/26/2009] [Accepted: 01/30/2009] [Indexed: 11/29/2022]
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Smith JL, Butler JE, Martin PG, McBain RA, Taylor JL. Increased ventilation does not impair maximal voluntary contractions of the elbow flexors. J Appl Physiol (1985) 2008; 104:1674-82. [DOI: 10.1152/japplphysiol.01358.2007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Exercise performance is impaired by increased respiratory work, yet the mechanism for this is unclear. This experiment assessed whether neural drive to an exercising muscle was affected by cortically driven increases in ventilation. On each of 5 days, eight subjects completed a 2-min maximal voluntary contraction (MVC) of the elbow flexor muscles, followed by 4 min of recovery, while transcranial magnetic stimulation tested for suboptimal neural drive to the muscle. On 1 day, subjects breathed without instructions under normocapnia. During the 2-min MVC, ventilation was ∼3.5 times that at rest. On another day, subjects breathed without instruction under hypercapnia. During the 2-min MVC, ventilation was ∼1.5 times that on the normocapnic day. On another 2 days under normocapnia, subjects voluntarily matched their breathing to the uninstructed breathing under normocapnia and hypercapnia using target feedback of the rate and inspiratory volume. On a fifth day under normocapnia, the volume feedback was set to each subject's vital capacity. On this day, ventilation during the 2-min MVC was approximately twice that on the uninstructed normocapnic day (or ∼7 times rest). The experimental manipulations succeeded in producing voluntary and involuntary hyperpnea. However, maximal voluntary force, fatigue and voluntary activation of the elbow flexor muscles were unaffected by cortically or chemically driven increases in ventilation. Results suggest that any effects of increased respiratory work on limb exercise performance are not due to a failure to drive both muscle groups optimally.
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O'Callaghan C, White J, Jackson J, Crosby D, Dougill B, Bland H. The effects of Heliox on the output and particle-size distribution of salbutamol using jet and vibrating mesh nebulizers. ACTA ACUST UNITED AC 2008; 20:434-44. [PMID: 18158716 DOI: 10.1089/jam.2007.0614] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
There are theoretical benefits of delivering drug aerosols to patients with asthma and chronic obstructive pulmonary disease (COPD) using Heliox as a carrier gas. The objective of this study was to develop systems to allow bronchodilators nebulized by a breath enhanced jet nebulizer and a vibrating mesh nebulizer to be delivered to patients in Heliox. This was achieved by attaching a reservoir to the nebulizers to ensure inhaled Heliox was not diluted by entrained air. For the vibrating mesh nebulizer, the total output was significantly higher after 5 min of nebulization when Heliox rather than air was used as the delivery gas (p < 0.001). The proportion of drug in particles <5 microm was 58.1% for Heliox and 50.1% when air was entrained. When the breath enhanced nebulizer was used a much higher driving flow of Heliox, compared to air, was required to deliver a similar dose of drug (p < 0.05). The total amount of drug likely to be inhaled was significantly higher when the vibrating mesh nebulizer (Aerogen) was used compared to the breath enhanced jet nebulizer (Pari LC plus) (p < 0.001). The amount of drug likely to be inhaled was also significantly greater for the adult as opposed to pediatric breathing pattern for all nebulizers and flows tested with the exception of the Aeroneb and Heliox entrainment. In this case, total amounts were similar for both patterns but for the pediatric pattern, the time taken to reach this output was longer. Such information is required to allow appropriate interpretation of clinical trials of drug delivery using Heliox.
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Affiliation(s)
- Christopher O'Callaghan
- Department of Infection, Immunity and Inflammation, Division of Child Health, University of Leicester, Leicester Royal Infirmary, Leicester, United Kingdom.
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Abstract
Chronic obstructive pulmonary disease (COPD) is characterized by poorly reversible airflow limitation. The pathological hallmarks of COPD are inflammation of the peripheral airways and destruction of lung parenchyma or emphysema. The functional consequences of these abnormalities are expiratory airflow limitation and dynamic hyperinflation, which then increase the elastic load of the respiratory system and decrease the performance of the respiratory muscles. These pathophysiologic features contribute significantly to the development of dyspnea, exercise intolerance and ventilatory failure. Several treatments may palliate flow limitation, including interventions that modify the respiratory pattern (deeper, slower) such as pursed lip breathing, exercise training, oxygen, and some drugs. Other therapies are aimed at its amelioration, such as bronchodilators, lung volume reduction surgery or breathing mixtures of helium and oxygen. Finally some interventions, such as inspiratory pressure support, alleviate the threshold load associated to flow limitation. The degree of flow limitation can be assessed by certain spirometry indexes, such as vital capacity and inspiratory capacity, or by other more complexes indexes such as residual volume/total lung capacity or functional residual capacity/total lung capacity. Two of the best methods to measure flow limitation are to superimpose a flow–volume loop of a tidal breath within a maximum flow–volume curve, or to use negative expiratory pressure technique. Likely this method is more accurate and can be used during spontaneous breathing. A definitive definition of dynamic hyperinflation is lacking in the literature, but serial measurements of inspiratory capacity during exercise will document the trend of end-expiratory lung volume and allow establishing relationships with other measurements such as dyspnea, respiratory pattern, exercise tolerance, and gas exchange.
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Affiliation(s)
- Luis Puente-Maestu
- Hospital General Universitario Gregorio Marañón, Servicio de Neumologia, Madrid, Spain.
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Mitchell GS, Babb TG. Layers of exercise hyperpnea: modulation and plasticity. Respir Physiol Neurobiol 2006; 151:251-66. [PMID: 16530024 DOI: 10.1016/j.resp.2006.02.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Revised: 02/02/2006] [Accepted: 02/03/2006] [Indexed: 11/23/2022]
Abstract
Despite the fundamental biological significance of the ventilatory response to mild or moderate physical activity (the exercise hyperpnea), we still know remarkably little concerning its underlying mechanisms. Part of the difficulty in revealing those mechanisms may arise due to confusion between multiple mechanistic layers, each contributing to the impressive degree of regulation achieved. The primary, feedforward exercise stimulus or stimuli increase ventilation in approximate proportion to changes in metabolic rate. Chemoreceptor feedback then minimizes deviations from optimal blood gas regulation, most often preventing excessive hypocapnia in non-human mammals. Recent evidence has accumulated, suggesting that adaptive control strategies including modulation and plasticity may adjust the feedforward and/or feedback contributions when blood gas homeostasis proves inadequate. In this review, we present evidence from a goat model of exercise hyperpnea concerning the existence of modulation and plasticity, and specifically mechanisms known as short-term and long-term modulation of the exercise ventilatory response. Throughout the review, we consider available evidence concerning the relevance of these mechanisms to humans. Plasticity is a property only recently recognized in the neural system subserving respiratory control, and the application of these concepts to the exercise ventilatory response in humans is in its infancy. Modulation and plasticity may confer an ability of individuals to adapt their exercise ventilatory response so that it remains appropriate in the face of life-long changes in endogenous (e.g. development, aging, onset of disease) or exogenous (e.g. altitude, wearing a breathing apparatus during physical exertion) physiological conditions.
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Affiliation(s)
- Gordon S Mitchell
- Department of Comparative Biosciences, University of Wisconsin, 2015 Linden Drive, Madison, WI 53706, USA.
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Tessitore A, Meeusen R, Tiberi M, Cortis C, Pagano R, Capranica L. Aerobic and anaerobic profiles, heart rate and match analysis in older soccer players. ERGONOMICS 2005; 48:1365-77. [PMID: 16338706 DOI: 10.1080/00140130500101569] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The aim of the present study was to provide aerobic (maximal oxygen consumption--VO2max) and anaerobic [jump tests: counter-movement jump (CMJ) and bounce jump (BJ); and running tests: 10 m sprint and 10 m dribbling the ball (10 mDB)] profiles of older soccer players (n = 12), and heart rate (HR), blood lactate accumulation (La) and match analysis (individual motor activity and team behaviour) aspects of a soccer match. The maximal aerobic test values were: HRmax, 154 +/- 14 beat min(-1); maximal power, 160 +/- 24 W; VO2peak, 36.3 +/- 11.3 ml kg(-1) min(-1); peak La, 8.2 +/- 1.8 mM. Jump test values were: CMJ, 21.2 +/- 4.5 cm; BJ, 17.3 +/- 4.8 cm. Running performances were: 10 m sprint, 2.06 +/- 0.36 s; 10 mDB, 2.17 +/- 0.21 s. Running showed similar values in the two halves (first half, 82%; second half, 88%), while walking lasted longer during the second half. Regarding the technical aspects of the match, 42% of the consecutive passes made in possession of the ball exceeded three passes, indicating that their play was structured in a cooperative manner. Older soccer players succeeded in maintaining good aerobic and anaerobic physical capability.
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Affiliation(s)
- Antonio Tessitore
- Department of Human Movement and Sport Science, IUSM of Rome, Pza L. De Bosis, 15-00194 Rome, Italy.
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Ge RL, Stone JA, Levine BD, Babb TG. Exaggerated respiratory chemosensitivity and association with level at 3568m in obesity. Respir Physiol Neurobiol 2005; 146:47-54. [PMID: 15733778 DOI: 10.1016/j.resp.2004.11.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2004] [Revised: 10/19/2004] [Accepted: 11/15/2004] [Indexed: 11/24/2022]
Abstract
To investigate whether obesity is associated with alterations in respiratory chemosensitivity, we compared the ventilatory response to hypoxia (HVR) and hypercapnia (HCVR) in 9 obese men (BMI: 37.0+/-4.3 kg m(-2)) and 10 lean men (BMI: 25.8+/-4.8 kg m(-2)). HVR (DeltaVE, L min(-1) per DeltaSaO2, %) was measured by a progressive isocapnic hypoxia technique, and HCVR (DeltaVE/DeltaPETCO2, L min(-1)Torr(-1)) was measured by a progressive hypercapnic method. HCVR, was greater (p<0.001) in the obese men (2.68+/-0.78) than in the lean men (1.4+/-0.45) as was HVR (p<0.05) (1.26+/-0.65 versus 0.71+/-0.43, respectively). The difference (DeltaSaO2, 4.30+/-3.69 and 10.54+/-3.45 in the lean and obese men, respectively, p<0.01) between daytime (86+/-1 and 86+/-1%) and nighttime SaO2 (81+/-3 and 76+/-4%) at a simulated altitude of 3658 m was significantly (p<0.05) correlated with both HVR (r=0.51) and HCVR (r=0.48). These results suggest that chemosensitivity in mildly obese men is increased, not blunted. Furthermore, otherwise healthy, obese individuals have the potential for significant desaturation during sleep at high altitude possibly due to exaggerated sleep-disordered breathing.
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Affiliation(s)
- Ri-Li Ge
- Research Center for High Altitude Medicine, Qinghai Medical College, 16 Kunlun Road, Xining, Qinghai 180001, PR China
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Corcoran TE, Gamard S. Development of Aerosol Drug Delivery with Helium Oxygen Gas Mixtures. ACTA ACUST UNITED AC 2004; 17:299-309. [PMID: 15684730 DOI: 10.1089/jam.2004.17.299] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Aerosol drug delivery using helium-oxygen gas mixtures (heliox) is considered in terms of flow physics, atomization, and aerosol mechanics. Theoretical considerations are then related to past studies of the physiological effects of the inhalation of heliox and its potential use as a drug delivery medium. Past clinical trials of heliox investigating this use are reviewed and technical recommendations made for its successful development. It is proposed that improved peripheral lung drug delivery with heliox is highly dependent on proper administration, especially the inclusion of proper reservoir system for the gas.
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Affiliation(s)
- T E Corcoran
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
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