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1.
Mickleborough TD Stager JM Chatham K Lindley MR Ionescu AA 《European journal of applied physiology》2008,103(6):635-646
Because the anomalous respiratory characteristics of competitive swimmers have been suggested to be due to inspiratory muscle work, the respiratory muscle and pulmonary function of 30 competitively trained swimmers was assessed at the beginning and end of an intensive 12-week swim training (ST) program. Swimmers (n = 10) combined ST with either inspiratory muscle training (IMT) set at 80% sustained maximal inspiratory pressure (SMIP) with progressively increased work-rest ratios until task failure for 3-days per week (ST + IMT) or ST with sham-IMT (ST + SHAM-IMT, n = 10), or acted as controls (ST only, ST, n = 10). Measures of respiratory and pulmonary function were assessed at the beginning and end of the 12 week study period. There were no significant differences (P > 0.05) in respiratory and pulmonary function between groups (ST + IMT, ST + SHAM-IMT and ST) at baseline and at the end of the 12 week study period. However, within all groups significant increases (P < 0.05) were observed in a number of respiratory and pulmonary function variables at the end of the 12 week study, such as maximal inspiratory and expiratory pressure, inspiratory power output, forced vital capacity, forced expiratory and inspiratory volume in 1-s, total lung capacity and diffusion capacity of the lung. This study has demonstrated that there are no appreciable differences in terms of respiratory changes between elite swimmers undergoing a competitive ST program and those undergoing respiratory muscle training using the flow-resistive IMT device employed in the present study; as yet, the causal mechanisms involved are undefined. 相似文献
2.
Barbalho-Moulim MC Miguel GP Forti EM Campos Fdo A Costa D 《Clinics (S?o Paulo, Brazil)》2011,66(10):1721-1727
OBJECTIVE:
To determine whether preoperative inspiratory muscle training is able to attenuate the impact of surgical trauma on the respiratory muscle strength, in the lung volumes, and diaphragmatic excursion in obese women undergoing open bariatric surgery.DESIGN:
Randomized controlled trial.SETTING:
Meridional Hospital, Cariacica/ES, Brazil.SUBJECTS:
Thirty-two obese women undergoing elective open bariatric surgery were randomly assigned to receive preoperative inspiratory muscle training (inspiratory muscle training group) or usual care (control group).MAIN MEASURES:
Respiratory muscle strength (maximal static respiratory pressure – maximal inspiratory pressure and maximal expiratory pressure), lung volumes, and diaphragmatic excursion.RESULTS:
After training, there was a significant increase only in the maximal inspiratory pressure in the inspiratory muscle training group. The maximal expiratory pressure, the lung volumes and the diaphragmatic excursion did not show any significant change with training. In the postoperative period there was a significant decrease in maximal inspiratory pressure in both the groups. However, there was a decrease of 28% in the inspiratory muscle training group, whereas it was 47% in the control group. The decrease in maximal expiratory pressure and in lung volumes in the postoperative period was similar between the groups. There was a significant reduction in the measures of diaphragmatic excursion in both the groups.CONCLUSION:
The preoperative inspiratory muscle training increased the inspiratory muscle strength (maximal inspiratory pressure) and attenuated the negative postoperative effects of open bariatric surgery in obese women for this variable, though not influencing the lung volumes and the diaphragmatic excursion. 相似文献3.
We investigated the effect of 4 week of inspiratory (IMT) or expiratory muscle training (EMT), as well as the effect of a
subsequent 6 week period of combined IMT/EMT on rowing performance in club-level oarsmen. Seventeen male rowers were allocated
to either an IMT (n = 10) or EMT (n = 7) group. The groups underwent a 4 week IMT or EMT program; after interim testing, both groups subsequently performed a
6 week program of combined IMT/EMT. Exercise performance and physiological responses to exercise were measured at 4 and 10 week
during an incremental rowing ergometer ‘step-test’ and a 6 min all-out (6MAO) effort. Pressure threshold respiratory muscle
training was undertaken at the 30 repetition maximum load (∼50% of the peak inspiratory and expiratory mouth pressure, P
Imax or P
Emax, respectively). P
Imax increased during the IMT phase of the training in the IMT group (26%, P < 0.001) and was accompanied by an improvement in mean power during the 6MAO (2.7%, P = 0.015). Despite an increase in P
Emax by the end of the intervention (31%, P = 0.03), the EMT group showed no significant changes in any performance parameters during either the ‘step-test’ or 6MAO.
There were no significant changes in breathing pattern or the metabolic response to the 6MAO test in either group, but the
IMT group showed a small decrease in HR (2–5%, P = 0.001). We conclude that there were no significant additional changes following combined IMT/EMT. IMT improved rowing performance,
but EMT and subsequent combined IMT/EMT did not. 相似文献
4.
Respiratory muscle strength training (RMST) is an exercise-based intervention which targets respiratory muscle weakness. We implemented RMST in two patients with late-onset Pompe disease (LOPD), both who had received long-term enzyme replacement therapy and had severe respiratory weakness. Over 16–32 weeks, inspiratory muscle strength increased by 73–74%. Expiratory muscle strength increased 31–48% over 12–22 weeks. These findings suggest that RMST may increase respiratory muscle strength, even in the setting of LOPD and severe baseline weakness. 相似文献
5.
Inspiratory and expiratory pressures are increased during expiratory resistive loading (ERL). We asked whether ERL elicits inspiratory as well as expiratory muscle fatigue. On four separate days, seven male subjects underwent ERL to task failure. Subjects maintained respiratory frequency at 15 breaths min−1, expiratory gastric pressure at 40% or 60% of maximum, and expiratory duty cycle at 0.4 or 0.7 (ERL40%0.4, ERL40%0.7, ERL60%0.4, ERL60%0.7). Inspiratory and abdominal muscle contractility was assessed before and up to 30 min after ERL by measuring transdiaphragmatic twitch pressure (Pdi,tw) and gastric twitch pressure (Pga,tw) in response to magnetic nerve stimulation. After each trial, Pdi,tw and Pga,tw were reduced below baseline values (−9 to −15% for Pdi,tw and −15 to −22% for Pga,tw; P < 0.05). The severity of diaphragm fatigue was unaffected by expiratory pressure production or expiratory duty cycle, whereas extending the expiratory duty cycle increased the severity of abdominal muscle fatigue. In conclusion, ERL elicits contractile fatigue of the diaphragm and the abdominal muscles. 相似文献
6.
Summary The morphological effects of daily bouts of exercise and denervation on teres minor intrafusal muscle fibers were investigated in male Sprague-Dawley rats. After denervation, nuclear bag and nuclear chain muscle fiber cross-sectional area atrophied only 25 and 33% of the amount experienced by extrafusal fibers. Of the two fiber types, the nuclear chain fibers appeared to be more responsive to the effects of exercise than the nuclear bag fibers; however, this trend for enlargement had no statistical significance. Length measurements did not reveal any marked changes of any fiber type to the experimental conditions of this study. It was concluded that the possible differences in function and innervation of the nuclear bag and nuclear chain fibers could partly account for these findings.Supported in part by funds provided by the Graduate College. 相似文献
7.
Thirty-three college men participated in a 9-week endurance training program. An equal number of subjects served as controls.
Pre- and post-test metabolic measurements were made during 10 min of submaximal exercise (1080 kpm/min at 60 rpm) and 15 min
of recovery. Measurements included oxygen consumption, CO2 production, ventilatory equivalent (V
E/VO2 ratio) and respiratory exchange ratio (R). A three factor design variance analysis was used to analyze the effects of training on min-by-min exercise and recoveryV
E/VO2 ratio andR. For the experimental group training resulted in a significant improvement in ventilatory efficiency during exercise, as
well as a significant decrease inR. During recovery,V
E/VO2 andR decreased significantly for both groups although the magnitude of change was greater for the group that trained. Apparently,
there was a significant habituation effect due to test procedures for the control group. The results are discussed in terms
of lactate production and substrate utilization during exercise. 相似文献
8.
Leddy JJ Limprasertkul A Patel S Modlich F Buyea C Pendergast DR Lundgren CE 《European journal of applied physiology》2007,99(6):665-676
The effects of voluntary isocapnic hyperpnea (VIH) training (10 h over 4 weeks, 30 min/day) on ventilatory system and running
performance were studied in 15 male competitive runners, 8 of whom trained twice weekly for 3 more months. Control subjects
(n = 7) performed sham-VIH. Vital capacity (VC), FEV1, maximum voluntary ventilation (MVV), maximal inspiratory and expiratory mouth pressures, 4-mile run time, treadmill run time to exhaustion at 80% serum lactate, total ventilation oxygen consumption oxygen saturation and cardiac output were measured before and after 4 weeks of VIH. Respiratory parameters and 4-mile run
time were measured monthly during the 3-month maintenance period. There were no significant changes in post-VIH VC and FEV1 but MVV improved significantly (+10%). Maximal inspiratory and expiratory mouth pressures, arterial oxygen saturation and
cardiac output did not change post-VIH. Respiratory and running performances were better 7- versus 1 day after VIH. Seven
days post-VIH, respiratory endurance (+208%) and treadmill run time (+50%) increased significantly accompanied by significant
reductions in respiratory frequency (−6%), (−7%), (−6%) and lactate (−18%) during the treadmill run. Post-VIH 4-mile run time did not improve in the control group whereas
it improved in the experimental group (−4%) and remained improved over a 3 month period of reduced VIH frequency. The improvements
cannot be ascribed to improved blood oxygen delivery to muscle or to psychological factors. 相似文献
9.
Effects of isokinetic training of the knee extensors on high-intensity exercise performance and skeletal muscle buffering 总被引:1,自引:0,他引:1
A. F. Mannion P. M. Jakeman P. L. T. Willan 《European journal of applied physiology》1994,68(4):356-361
Twenty-three subjects isokinetically trained the right and left quadriceps femoris, three times per week for 16 weeks; one group (n=13) trained at an angular velocity of 4.19 rad · s–1 and a second group (n=10), at 1.05 rad · s–1. A control group (n=10) performed no training. Isometric endurance time at 60% quadriceps maximum voluntary contraction (MVC), mean power output and work done (W) during all-out cycling, and the muscle buffer value (B) and carnosine concentration of biopsy samples from the vastus lateralis, were all assessed before and after training. The two training groups did not differ significantly from each other in their training response to any of these variables (P < 0.05). No significant difference in either 60% MVC endurance time or impulse [(endurance time × force) at 60% MVC] was observed for any group after the 16 week period (P > 0.05). However, the post-training increase (9%) in W during high-intensity cycling was greater in the training group than in the control group (P=0.04). NeitherB nor carnosine concentration showed any significant change following training (P=0.56 andP=0.37, respectively). It is concluded that 16 weeks of isokinetic training of the knee extensors enables subjects to do more work during high-intensity cycling. Although the precise adaptations responsible for the improved performance have yet to be identified, they are unlikely to include an increase inB. 相似文献
10.
This study investigated the relationship between the intensity of an inspiratory muscle training programme and its effect on respiratory muscle strength, exercising heart rate, and ratings of perceived exertion. A total of 66 subjects were randomly assigned to one of three groups. One group trained at 100% of maximum inspiratory pressure (MIP) for 6 weeks (MAX, n=22). A second group performed 6 weeks of inspiratory muscle training at 80% of MIP (SUB, n=21) and a third control group received no inspiratory training (CON, n=23). Both the MAX and SUB training groups improved MIP relative to the control group [32 (19) cmH2O, P=0.01; 37 (25) cmH2O, P=0.001, respectively]. A significant decrease in heart rate [–6 (9) beats min–1, P=0.02] and rating of perceived exertion [–0.5 (1.4), P=0.04] was observed for the MAX group only. It is concluded that 6 weeks of both MAX and SUB training were sufficient to improve inspiratory muscle strength. However, exercising heart rate and perceived exertion decreased with MAX training only. 相似文献
11.
Shinichi Saitoh Yoshiharu Shimomura Yousuke Tasaki Masashige Suzuki 《European journal of applied physiology》1992,64(1):62-67
Summary It has been reported that exercise training increases muscle glycogen storage in rats fed a high carbohydrate (CHO) diet in resting conditions. The purpose of this study was to examine whether a 3-week swimming training programme would increase muscle glycogen stores in rats fed a high-fat (FAT) diet in resting conditions. Rats were fed either the FAT or CHO diet for 7 days ad libitum, and then were fed regularly twice a day (between 0800 and 0830 hours and 1800 and 1830 hours) for 32 days. During this period of regular feeding, half of the rats in both dietary groups had swimming training for 3 weeks and the other half were sedentary. The rats were not exercised for 48 h before sacrifice. All rats were killed 2 h after their final meal (2030 hours). The glycogen contents in red gastrocnemius muscle, heart and liver were significantly higher in sedentary rats fed the CHO diet than in those fed the FAT diet. Exercise training clearly increased glycogen content in soleus, red gastrocnemius and heart muscle in rats fed the CHO diet. In rats fed the FAT diet, however, training did not increase glycogen content in these muscles or the heart. Exercise training resulted in an 87% increase of total glycogen synthase activity in the gastrocnemius muscle of rats fed the CHO diet. However, this was not observed in rats fed the FAT diet. The total glycogen phosphorylase activity in the gastrocnemius muscle of the rats of both dietary groups was increased approximately twofold by training. These results suggested that muscle glycogen was enhanced in rats fed the CHO diet and that the glycogen content of the muscle of rats fed the FAT diet was not increased by exercise training. 相似文献
12.
The functional outcomes of respiratory muscle loading by chemical (e.g. hypercapnia), mechanical (i.e. external mechanical loading) or ventilatory (e.g. exercise) factors can be either positive, such as through an increase in pressure-generating capacity of the inspiratory muscles or detrimental, such as by fatigue. Neurophysiological responses to respiratory muscle loading can occur at one or more points along the pathway from motor cortex to muscle. This paper describes the respiratory pump and upper airway motoneuron responses to the imposition of acute loads including processes of pre-activation, respiratory reflexes, potentiation and fatigue. It also considers changes suggestive of adaptation to chronic loading either from specific respiratory muscle training programs or as part of disease processes such as chronic obstructive pulmonary disease or obstructive sleep apnoea. 相似文献
13.
Effects of training at simulated altitude on performance and muscle metabolic capacity in competitive road cyclists 总被引:2,自引:0,他引:2
Nicolas Terrados Jan Melichna Christer Sylvén Eva Jansson Lennart Kaijser 《European journal of applied physiology》1988,57(2):203-209
Summary Differences between the effects of training at sea level and at simulated altitude on performance and muscle structural and biochemical properties were investigated in 8 competitive cyclists who trained for 3–4 weeks, 4–5 sessions/week, each session consisting of cycling for 60–90 min continuously and 45–60 min intermittently. Four subjects, the altitude group (AG), trained in a hypobaric chamber (574 torr=2300 m above sea level), and the other four at sea level (SLG). Before and after training work capacity was tested both at simulated altitude (574 torr) and at sea level, by an incremental cycle ergometer test until exhaustion. Work capacity was expressed as total amount of work performed. Venous blood samples were taken during the tests. Leg muscle biopsies were taken at rest before and after the training period. AG exhibited an increase of 33% in both sea level and altitude performance, while SLG increased 22% at sea level and 14% at altitude. Blood lactate concentration at a given submaximal load at altitude was significantly more reduced by training in AG than SLG. Muscle phosphofructokinase (PFK) activity decreased with training in AG but increased in SLG. All AG subjects showed increases in capillary density. In conclusion, work capacity at altitude was increased more by training at altitude than at sea level. Work capacity at sea level was at least as much improved by altitude as by sea level training. The improved work capacity by training at altitude was paralleled by decreased exercise blood lactate concentration, increased capillarization and decreased glycolytic capacity in leg muscle. 相似文献
14.
R. C. Hickson J. M. Hagberg R. K. Conlee D. A. Jones A. A. Ehsani W. W. Winder Ph.D. 《European journal of applied physiology》1979,41(3):211-219
Summary The effects of 9 weeks of training on responses of plasma hormones to swimming were studied in eight competitive swimmers who had not trained for several months. Two types of swimming tests were used: (1) 200 yd, a high intensity, exhausting type of exercise in which maximal effort was required both before and after training, and (2) 1000 yd, a pace type of exercise in which subjects swam as fast as possible prior to training and at the same rate after training. Plasma levels of glucagon increased and of insulin decreased during 1000 yd of swimming, but were not altered by 200 yd of swimming. No training effects were apparent in responses of plasma insulin and glucagon to these short-term, high intensity exercise tests. During the 1000 yd swim, plasma adrenaline was 0.8 ng/ml before vs. 0.1 ng/ml after training. Plasma noradrenaline response decreased from 3.4 to 1.2 ng/ml as a result of training. In the 200 yd swim, adrenaline, but not noradrenaline, was lower after training.R. C. Hickson and R. K. Conlee were postdoctoral research trainees supported by NIH Training Grant AM-05341.J. M. Hagberg was a postdoctoral research trainee supported by NIH Training Grant HL-07081. 相似文献
15.
Boussana A Hue O Matecki S Galy O Ramonatxo M Varray A Le Gallais D 《European journal of applied physiology》2002,87(4-5):441-447
This study investigated the possibility of there being differences in respiratory muscle strength and endurance in elite
and competition triathletes who have similar maximal oxygen uptakes (VO2max) and ventilatory thresholds (Thvent). Five internationally-ranked elite, [mean (SD) age 23.8 (1.4) years] and six nationally- and regionally-ranked competition
[age 21.1 (1.1) years] male triathletes performed two successive trials: first an incremental cycle test to assess VO2max and Thvent and second 20 min of cycling followed by 20 min of running (C-R) at intensities higher than 85% VO2max. Cardioventilatory data were collected every minute during the two trials, using an automated breath-by-breath system. Maximal
expiratory and inspiratory (P
Imax) strength were assessed before and 10 min after C-R from the functional residual capacity. Respiratory muscle endurance was
assessed 1 day before and 30 min after C-R by measuring the time limit (t
lim). The results showed firstly that during C-R, the competition triathletes had significantly (P<0.05) higher minute ventilation [mean (SEM) 107.4 (3.1) compared to 99.8 (3.7) l·min–1], breathing frequency [44.4 (2.0) compared to 40.2 (3.4) ·min–1] and heart rate [166 (3) compared to 159 (4) beats·min–1] and secondly that after C-R, they had significantly lower P
Imax [127.1 (4.2) compared to 130.7 (3.0) cmH2O] and tlim [2:35 (0:29) compared to 4:12 (0:20) min] than the elite triathletes. We conclude that, despite similar VO2max and Thvent, the competition triathletes showed less extensive adaptive mechanisms, including those in the respiratory muscles, than
did the elite triathletes. This led to higher ventilation, which appeared to be the cause of the faster development of fatigue
in the inspiratory muscles in this group.
Electronic Publication 相似文献
16.
John L. Ewing Jr. D. Roy Wolfe Marc A. Rogers Mark L. Amundson G. Alan Stull 《European journal of applied physiology》1990,61(1-2):159-162
Summary Twenty young men trained the right knee extensors and flexors on an isokinetic dynamometer three times weekly over a 10-week period. During each session, 10 men in the slow training group completed three sets of 8 maximal contractions at a rate of 1.05 rad s–1, whereas the other 10, the fast group, completed three sets of 20 contractions at a rate of 4.19 rad s–1. Subjects were pre- and post-tested for peak torque and power on an isokinetic dynamometer at 1.05, 3.14, and 4.19 rad s–1. Proportions of muscle fibre-types and fibre cross-sectional areas were determined from biopsy specimens taken before and after training from the right vastus lateralis. When testing was conducted at 1.05 rad s–1, the slow group improved (P<0.05) peak torque by 24.5 N m (8.5%), but no change was noted for the fast group. Power increased (P< 0.05) by 32.7 W (13.6%) in the slow group and 5.5 W (2.5%) in the fast. At 3.14 rad s–1, both groups increased (P<0.05) peak torque and power. At 4.19 rad s–1, the fast group increased (P<0.05) peak torque by 30.0 N m (19.7%), whereas no training effect was observed in the slow group. There was no significant change in power in either group at 4.19 rad s–1, No significant changes were observed over the 10-week training period in percentages of type I, IIa and IIb fibres, but both groups showed significant increases (P<0.05) in type I and IIa fibre areas. No differences were noted between groups, and no hypertrophy of type IIb fibres was observed. 相似文献
17.
Eric Verin Christian Delafosse Christian Straus Capucine Morélot-Panzini Sergeï Avdeev Jean-Philippe Derenne Thomas Similowski 《European journal of applied physiology》2001,85(6):593-598
Measuring maximal sniff pressures is an easy way of assessing inspiratory muscle strength. During a static manoeuvre, the
pattern of inspiratory muscle recruitment during a sniff can vary from one individual to another. We therefore assessed how
voluntarily changing muscle recruitment would affect sniff oesophageal, gastric and transdiaphragmatic pressures (Pes,sn, Pga,sn and Pdi,sn, respectively). Ten normal subjects (age 27–38 years) performed natural sniff manoeuvres ("nat"), and preferentially
diaphragmatic ("dia") or extradiaphragmatic ("extradia") sniff manoeuvres, after having learnt to dissociate between the inspiratory
muscle groups. Abdominal displacements were monitored using a belt-mounted strain gauge. Natural patterns of muscle recruitment
varied among subjects. On average, Pes,sn,nat was [median (range)] 81 (21–105) cmH2O. All of the subjects were able to modify inspiratory muscle recruitment voluntarily. Pes,sn was not significantly affected by the type of manoeuvre performed, as opposed to Pdi,sn, which, as expected, increased with both the diaphragmatic and extradiaphragmatic manoeuvres [Pdi,sn,dia 132 (99–157) cmH2O, Pdi,sn,extradia 96 (50–146) cmH2O, P<0.05]. Whatever the manoeuvre, there was no correlation between Pes and Pdi, but Pga and Pdi were correlated during both the diaphragmatic (r=0.82, P<0.05) and the extradiaphragmatic manoeuvre (r=0.70, P< 0.05). Pes,sn may have limitations as an index of diaphragm function, but by showing its independence from inspiratory muscle recruitment,
this study contributes to its validation as a robust index of global inspiratory muscle strength that is particularly well
suited for follow-up studies. This should extend to Pes,sn substitutes measured at the airway opening.
Electronic Publication 相似文献
18.
C.S.C. Trevisan A.S. Garcia-Araújo A.C.G.O. Duarte V.O. Furino T.L. Russo A. Fujimoto H.C.D. Souza R.B. Jaenisch R. Arena A. Borghi-Silva 《Brazilian journal of medical and biological research》2021,54(7)
This study verified the effects of respiratory muscle training (RMT) on hemodynamics, heart rate (HR) variability, and muscle morphology in rats with streptozotocin-induced diabetes mellitus (DM). Thirty-six male Wistar rats were randomized into 4 groups and 34 completed the study: i) sham-sedentary (Sham-ST; n=9); ii) sham-RMT (Sham-RMT; n=9); iii) DM-sedentary (DM-ST; n=8); and iv) DM-RMT (DM-RMT; n=8). Hemodynamics were assessed by central cannulation, and R-R intervals were measured by electrocardiogram. In addition, the effects of RMT on the cross-sectional area of the diaphragm, anterior tibial, and soleus muscles were analyzed. The induction of DM by streptozotocin resulted in weight loss, hyperglycemia, reduced blood pressure, and attenuated left ventricular contraction and relaxation (P<0.05). We also observed a decrease in root mean square of successive differences between adjacent RR intervals (RMSSD) index and in the cross-sectional area of the muscles assessed, specifically the diaphragm, soleus, and anterior tibial muscles in diabetic rats (P<0.05). Interestingly, RMT led to an increase in RMSSD in rats with DM (P<0.05). The induction of DM produced profound deleterious changes in the diaphragmatic and peripheral muscles, as well as impairments in cardiovascular hemodynamics and autonomic control. Nevertheless, RMT may beneficially attenuate autonomic changes and improve parasympathetic modulation. 相似文献
19.
Buchman AS Boyle PA Wilson RS Gu L Bienias JL Bennett DA 《Mechanisms of ageing and development》2008,129(11):625-631
Numerous reports have linked extremity muscle strength with mortality but the mechanism underlying this association is not known. We used data from 960 older persons without dementia participating in the Rush Memory and Aging Project to test two sequential hypotheses: first, that extremity muscle strength is a surrogate for respiratory muscle strength, and second, that the association of respiratory muscle strength with mortality is mediated by pulmonary function. In a series of proportional hazards models, we first demonstrated that the association of extremity muscle strength with mortality was no longer significant after including a term for respiratory muscle strength, controlling for age, sex, education, and body mass index. Next, the association of respiratory muscle strength with mortality was attenuated by more than 50% and no longer significant after including a term for pulmonary function. The findings were unchanged after controlling for cognitive function, parkinsonian signs, physical frailty, balance, physical activity, possible COPD, use of pulmonary medications, vascular risk factors including smoking, chronic vascular diseases, musculoskeletal joint pain, and history of falls. Overall, these findings suggest that pulmonary function may partially account for the association of muscle strength and mortality. 相似文献
20.
Wylegala JA Pendergast DR Gosselin LE Warkander DE Lundgren CE 《European journal of applied physiology》2007,99(4):393-404
Respiratory muscles can fatigue during prolonged and maximal exercise, thus reducing performance. The respiratory system is
challenged during underwater exercise due to increased hydrostatic pressure and breathing resistance. The purpose of this
study was to determine if two different respiratory muscle training protocols enhance respiratory function and swimming performance
in divers. Thirty male subjects (23.4 ± 4.3 years) participated. They were randomized to a placebo (PRMT), endurance (ERMT),
or resistance respiratory muscle training (RRMT) protocol. Training sessions were 30 min/day, 5 days/week, for 4 weeks. PRMT
consisted of 10-s breath-holds once/minute, ERMT consisted of isocapnic hyperpnea, and RRMT consisted of a vital capacity
maneuver against 50 cm H2O resistance every 30 s. The PRMT group had no significant changes in any measured variable. Underwater and surface endurance
swim time to exhaustion significantly increased after RRMT (66%, P < 0.001; 33%, P = 0.003) and ERMT (26%, P = 0.038; 38%, P < 0.001). Breathing frequency (f
b) during the underwater endurance swim decreased in RRMT (23%, P = 0.034) and tidal volume (V
T) increased in both the RRMT (12%, P = 0.004) and ERMT (7%, P = 0.027) groups. Respiratory endurance increased in ERMT (216.7%) and RRMT (30.7%). Maximal inspiratory and expiratory pressures
increased following RRMT (12%, P = 0.015, and 15%, P = 0.011, respectively). Results from this study indicate that respiratory muscle fatigue is a limiting factor for underwater
swimming performance, and that targeted respiratory muscle training (RRMT > ERMT) improves respiratory muscle and underwater
swimming performance. 相似文献