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1.
Vianna LC Oliveira RB Silva BM Ricardo DR Araújo CG 《European journal of applied physiology》2008,102(3):283-288
Post-exercise cardiac vagal reactivation is well-investigated; however, the effect of water intake during this period has
not been well studied. Therefore, our aim was to assess the influence of water intake on the cardiac vagal reactivation after
30 min of a submaximal cycling exercise. Ten healthy subjects (eight men) aged 23–35 years were evaluated. A 3-day testing
cycle duration, subjects were randomly chosen to drink either 500 ml (experimental visit) or 50 ml (control visit) of water
immediately after the 30-min cycling exercise at a workload representing 80% of a previously measured anaerobic threshold.
A cardiac vagal index (CVI) was obtained using the 4-s exercise test measured before and after (10 and 30 min) exercise at
each testing day. Data analysis (2 × 3 ANOVA for repeated measures) showed higher cardiac vagal activity at the 30-min post-exercise
period when 500 ml of water was ingested. CVI values for the 500 and 50 ml trials were 1.55 ± 0.04 vs. 1.49 ± 0.04, P = 0.003 (mean ± SEM), respectively. Heart rate and blood pressure values were relatively the same. In conclusion, water intake
of about 500 ml immediately after 30 min of cycling exercise accelerates post-exercise cardiac vagal reactivation. These results
suggest that post-exercise hydration might be beneficial not only for thermoregulation, but also for vagal reactivation. 相似文献
2.
LeMura LM von Duvillard SP Andreacci J Klebez JM Chelland SA Russo J 《European journal of applied physiology》2000,82(5-6):451-458
The purpose of this study was to evaluate the effects of various modes of training on the time-course of changes in lipoprotein-lipid
profiles in the blood, cardiovascular fitness, and body composition after 16 weeks of training and 6 weeks of detraining in
young women. A group of 48 sedentary but healthy women [mean age 20.4 (SD 1) years] were matched and randomly placed into
a control group (CG, n=12), an aerobic training group (ATG, n=12), a resistance training group (RTG, n=12), or a cross-training group that combined both aerobic and resistance training (XTG, n=12). The ATG, RTG and XTG trained for 16 weeks and were monitored for changes in blood concentrations of lipoprotein-lipids,
cardiovascular fitness, body composition, and dietary composition throughout a 16 week period of training and 6 weeks of detraining.
The ATG significantly reduced blood concentrations of triglycerides (TRI) (P < 0.05) and significantly increased blood concentrations of high-density lipoprotein-cholesterol (HDL-C) after 16 weeks of
training. The correlation between percentage fat and HDL-C was 0.63 (P < 0.05), which explained 40% of the variation in HDL-C, while the correlation between maximal oxygen uptake (V˙O2max) and HDL-C was 0.48 (P < 0.05), which explained 23% of the variation in HDL-C. The ATG increased V˙O2max by 25% (P < 0.001) and decreased percentage body fat by 13% (P < 0.05) after 16 weeks. Each of the alterations in the ATG had disappeared after the 6 week detraining period. The concentration
of total cholesterol (TC), TRI, HDL-C and low density lipoprotein-cholesterol in the blood did not change during the study
in RTG, XTG and CG. The RTG increased upper and lower body strength by 29% (P < 0.001) and 38%, respectively. The 6 week detraining strength values obtained in RTG were significantly greater than those
obtained at baseline. The XTG increased upper and lower body strength by 19% (P < 0.01) and 25% (P < 0.001), respectively. The 6 week detraining strength values obtained in XTG were significantly greater than those obtained
at baseline. The RTG, XTG and CG did not demonstrate any significant changes in either V˙O2max, or body composition during the training and detraining periods. The results of this study suggest that aerobic-type exercise
improves lipoprotein-lipid profiles, cardiorespiratory fitness and body composition in healthy, young women, while resistance
training significantly improved upper and lower body strength only.
Accepted: 9 April 2000 相似文献
3.
The effect of strength training and short-term detraining on maximum force and the rate of force development of older men 总被引:1,自引:0,他引:1
This study examined the effect of strength training (ST) and short-term detraining on maximum force and rate of force development
(RFD) in previously sedentary, healthy older men. Twenty-four older men (70–80 years) were randomly assigned to a ST group
(n = 12) and C group (control, n = 12). Training consisted of three sets of six to ten repetitions on an incline squat at 70–90% of one repetition maximum
three times per week for 16 weeks followed by 4 weeks of detraining. Regional muscle mass was assessed before and after training
by dual-energy X-ray absorptiometry. Training increased RFD, maximum bilateral isometric force, and force in 500 ms, upper
leg muscle mass and strength above pre-training values (14, 25, 22, 7, 90%, respectively; P < 0.05). After 4 weeks detraining all neuromuscular variables were significantly (P < 0.05) lower than after 16 weeks training but remained significantly (P < 0.05) higher than pre-training levels except for RFD which had returned to pre-training levels. These findings demonstrate
that high-intensity ST can improve maximum force and RFD of older men. However, older individuals may lose some neuromuscular
performance after a period of short-term detraining and that resistance exercise should be performed on a regular basis to
maintain training adaptations. 相似文献
4.
In cardiac rehabilitation, different endurance exercises such as walking and cycling are often performed. The training intensity
for these modes is determined from a single treadmill or bicycle test by ventilatory threshold (VT). In this study, differences
of VT between walking and cycling and agreement of VT between training modes were assessed in cardiac patients. A total of
46 cardiac rehabilitation patients (mean age 59.5 ± 8.4 years, 45 males) (31 untrained and 15 trained) completed a maximal
exercise test on bicycle and treadmill, with breath-by-breath analysis of oxygen uptake (VO2), carbon dioxide production and expiratory volume. VT was determined by V-slope method. Correlations of VT and VO2peak were calculated between exercise modes. Bland–Altman plots were made for determining VT agreement between modes. VT was significantly
different between walking and cycling in trained patients (P < 0.05), but not in untrained patients (P > 0.05). When untrained and trained patients were compared, VT correlation was lower (r = 0.50) in the former group, as compared to the latter group (r = 0.78). Also, Bland–Altman plots showed smaller limits of agreement for VT in trained (2 SD −1.6 to 7.8 ml/min/kg), as compared
to untrained patients (2 SD −7.0 to 9.6 ml/min/kg). In trained patients, VT correlates well between training methods, but
is highly exercise mode specific. In untrained patients, VT is not exercise mode specific, but the VT has a low correlation
between training modes. This study shows that VT should be assessed by the appropriate exercise model for determining exercise
intensity in cardiac rehabilitation. 相似文献
5.
Adiponectin is an anti-inflammatory protein that reduced in obesity. Exercise training may reduce the adipose tissue (AT),
although it is not well known whether exercise-induced change in AT, increases the adiponectin mRNA expression and plasma
concentrations or not; therefore, the purpose of this study was to investigate the adiponectin mRNA and plasma concentrations
in middle-aged men after 12 weeks high-intensity exercise training and after a week detraining. Sixteen sedentary overweight
and obese middle-aged men (age 41.18 ± 6.1 years; ± SD) volunteered to participate in this study. The subjects were randomly
assigned to training group (n = 8) or control group (n = 8). The training group performed endurance training 4 days a week for 12 weeks at an intensity corresponding to 75–80%
individual maximum oxygen consumption for 45 min. After 12 weeks of training, subjects underwent a week of detraining. The
results showed that the BMI as well as central and peripheral AT volume were decreased in the training group compared to the
control group (P < 0.05). After 12 weeks, the training group resulted in a significant increase (P < 0.05) in the adiponectin gene expression in abdominal and gluteal subcutaneous AT when compared with the control group.
The results showed that plasma adiponectin concentrations increased and insulin resistance decreased after training compared
to the control group (P < 0.05). After a week of detraining, the variables were not changed significantly in the training group. In conclusion, high-intensity
endurance training caused an increase adiponectin mRNA in obese middle-aged men. 相似文献
6.
J. BUCKWORTH V. A. CONVERTINO K. J. CURETON R.K. DISHMAN 《Acta physiologica (Oxford, England)》1997,160(1):29-41
The effects of exercise detraining on resting finger arterial blood pressure (BP), the carotid-cardiac vagal baroreflex, and BP and heart rate (HR) responses to mental arithmetic and forehead cold exposure were studied in young (19 ± 1.1 years) normotensive women with parental history of hypertension. Following 8 weeks of aerobic exercise for 25 min, 3 days week?1 at an intensity of 60% V˙O 2 peak, subjects ceased training for 6–8 weeks. After detraining, V˙O 2 peak (mL kg?1 min?1) was reduced by 11.5% (41.1 ± 6.9 to 36.4 ± 4.8) coincident with an ≈ 10 %increase in submaximal exercise heart rate. Responses to the laboratory tasks were then compared. Detraining was accompanied by increases (P <0.05) in resting systolic (SBP) (113.6 ± 8.9 to 121.2 ± 9.0), diastolic (DBP) (63.0 ± 8.4 to 68.3 ± 6.8), and mean arterial (MAP) (78.7 ±8.4 to 84.2 ± 7.3) BP (mmHg). None of the above changes occurred in sedentary matched-control subjects. Systolic blood pressure was elevated during forehead cold exposure and MAP was elevated during mental arithmetic after detraining, but the rates of response and recovery for SBP, DBP and MAP were not altered by detraining. Despite higher submaximal exercise HR after detraining, HR responses to autonomic challenges, including the carotid-cardiac vagal baroreflex, were unchanged between training and detraining. Our results indicate that exercise detraining increases resting finger arterial BP in young normotensive women at risk for hypertension with no effects on the rate of response or recovery of heart rate and BP during autonomic tasks known to elicit sympathetic and carotid-cardiac vagal activities in this population. The use of auscultatory brachial artery pressures in a similar study of women diagnosed with hypertension will clarify the clinical meaning of our findings. 相似文献
7.
Santa-Clara H Fernhall B Mendes M Sardinha LB 《European journal of applied physiology》2002,87(6):568-575
Weight-training is recommended as a complement to conventional aerobic-training for most low to moderate risk patients suffering
from coronary artery disease (CAD). The purpose of this study was to evaluate the effect of a 1 year exercise programme combining
weight- and aerobic-training on peak oxygen uptake (VO2,peak) and ventilatory threshold (VT). We studied 40 men suffering CAD who were divided into three groups: 14 subjects to weight-training
plus aerobic-training [mean (SD] [combined exercise group, age 55 (10) years], 14 to aerobic-training only [aerobic-training
group, age 57 (11) years], and 12 to a control group [standard care, age 57 (11) years]. A symptom-limited graded exercise
test using the standard Bruce protocol was performed using a 12-lead electrocardiogram, and gas analysis techniques. Muscle
strength was determined only in the combined exercise group using the one-repetition maximum method on each of eight weight
exercises. Arm and leg strength increased by 21.9% and 27.8% respectively (P<0.0001) from pre to post-tests. The VO2,peak did not differ between the combined and aerobic-training groups but their adjusted means were greater than those of the control
group [39 (1.8) and 35.3 (1.8) compared to 26.2 (2.7) ml·kg–1·min–1 (P<0.001)]. The oxygen uptake at VT was higher in the combined group [24.7 (1.4) ml·kg–1·min–1] compared to aerobic [18.7 (1.4) ml·kg–1·min–1] and control [13.6 (1.7) ml·kg–1min–1] groups (P<0.001). Similar results were found for exercise tolerance (treadmill time to peak and at VT). Combined exercise training
increased the VT more than aerobic-training alone. Combined exercise training did not improve the VO2,peak or the functional capacity more than aerobic-training alone.
Electronic Publication 相似文献
8.
Jason A. Melnyk Marc A. Rogers Ben F. Hurley 《European journal of applied physiology》2009,105(6):929-938
To examine the effects of 9 weeks of strength training (ST) and 31 weeks of detraining on regional muscle area in young and
older men and women, three regions of the quadriceps muscle area (proximal, middle, and distal) were measured via MRI in 11
men ages 20–30, 11 men ages 65–75, 10 women ages 20–30, and 11 women ages 65–75. These effects were assessed by determining
the difference between the control limb and the trained limb (T-UT) at all three time points. This design provided control
for possible influences of biological, methodological, seasonal variations, as well as influences due to attention or genetic
differences that commonly occur between experimental and control groups. There were no significant differences in any of the
three regions at any of the three time points, when comparing subjects by age. However, men had significantly greater T-UT
CSA at the after ST time point [6.9 (3.7) cm2] when compared with women [2.8 (3.7) cm2, P < 0.05]. Baseline T-UT CSA was higher than after detraining T-UT CSA for young men in the proximal and middle regions [0.1
(3.6), 0.4 (3.6) cm2 vs. 2.8 (4.0), 2.4 (3.6) cm2, P < 0.05], but there were no significant differences within the other three groups. These data indicate that sex may influence
changes in regional CSA after ST, whereas age does not influence regional muscle gain or loss due to ST or detraining. 相似文献
9.
Cross education of muscular strength during unilateral resistance training and detraining 总被引:2,自引:0,他引:2
Shima N Ishida K Katayama K Morotome Y Sato Y Miyamura M 《European journal of applied physiology》2002,86(4):287-294
Abstract. The purpose of the present study was to examine the changes in maximum voluntary isometric contraction (MVC) in the contralateral
untrained limb during unilateral resistance training and detraining, and to examine the factors inducing these changes by
means of electrophysiological techniques. Nine healthy males trained their plantar flexor muscles unilaterally 4 days·week–1 for 6 weeks using 3 sets of 10–12 repetitions at 70–75% of one-repetition maximum a day, and detrained for 6 weeks. Progressive
unilateral resistance training significantly (P<0.05) increased MVC, integrated electromyogram (iEMG), and voluntary activation in the trained and contralateral untrained
limbs. The changes in MVC after training were significantly correlated with the changes in iEMG in both limbs. No significant
changes occurred in MVC, voluntary activation, and iEMG in the contralateral limb after detraining. The changes in MVC after
detraining did not correlate with the changes in voluntary activation or iEMG in either limb. Training and detraining did
not alter twitch and tetanic peak torques in either limb. These results suggest that the mechanisms underlying cross education
of muscular strength may be explained by central neural factors during training, but not solely so during detraining.
Electronic Publication 相似文献
10.
Summary To elucidate the changes in neuro-muscular function during strength training and detraining, five male subjects underwent progressive isotonic strength training of their calf muscles three times a week for 8 weeks with additional detraining for the same periods. Electrically evoked twitch contractions were induced in the triceps surae muscles of each subject every 4 weeks during the training and detraining periods. At the same time, maximal voluntary isometric contractions (MVC) and the maximal girth of the calf (MGC) were measured. During the training period, MVC increased significantly from 98.4 to 129.6 Nm (31.7%, P < 0.01) for the first 4 weeks of training but MGC showed little increase. Neither of the changes correlated with each other. Twitch contraction parameters, i.e. maximal twitch torque (P
t
), maximal rate of torque development (max dT/dt) and rate of relaxation (relax dT/dt) showed no statistical change. During detraining, on the contrary, a large and significant increase (22.5%, P < 0.01) was observed in max dTldt without any changes in P
t
and relax dT/dt. The MVC/P
t
showed both significant increases during training and decreases during detraining. Our data suggest that short term strength training as employed in the present study does not induce changes in the contractile properties of the muscle during training, but may significantly affect the rate of force development during the subsequent detraining period, indicating the possible existence of complex post-training muscle adaptation. 相似文献
11.
Barnes MJ Perry BG Mündel T Cochrane DJ 《European journal of applied physiology》2012,112(3):1189-1194
The purpose of this study was to investigate the effects of acute vibration therapy (VT) on performance recovery after a bout
of strenuous eccentric exercise. Eight healthy males completed 300 maximal eccentric contractions of the quadriceps of one
leg on an isokinetic dynamometer. Immediately after exercise and 12 and 24 h post-exercise, the subjects underwent either
VT or a control treatment of no VT. Five sets of 1 min VT was performed at 26 Hz, with 6 mm peak-to-peak displacement, on
a commercially available vibration machine. At least 2 weeks after the initial trial, the subjects completed the second trial
using the contralateral leg and other treatment. Peak and average peak isometric tension and isokinetic concentric and eccentric
torque were measured prior to exercise and 24 and 48 h post-exercise. Treatment with VT resulted in significantly (all P < 0.05) greater decrements in peak (−38%) and average peak eccentric (−39%) torque 24 h after eccentric exercise as compared
to a control treatment (−24 and −29%, respectively). These results suggest that the use of 26 Hz VT in the first 24 h after
damaging exercise may be detrimental to the magnitude of force loss and/or recovery over this period. 相似文献
12.
Nutrition is an important co-factor in exercise-induced training adaptations in muscle. We compared the effect of 6 weeks
endurance training (3 days/week, 1–2 h at 75% VO2peak) in either the fasted state (F; n = 10) or in the high carbohydrate state (CHO, n = 10), on Ca2+-dependent intramyocellular signalling in young male volunteers. Subjects in CHO received a carbohydrate-rich breakfast before
each training session, as well as ingested carbohydrates during exercise. Before (pretest) and after (posttest) the training period, subjects performed a 2 h constant-load exercise bout (~70% of pretest VO2peak) while ingesting carbohydrates (1 g/kg h−1). A muscle biopsy was taken from m. vastus lateralis immediately before and after the test, and after 4 h of recovery. Compared
with pretest, in the posttest basal eukaryotic elongation factor 2 (eEF2) phosphorylation was elevated in CHO (P < 0.05), but not in F. In the pretest, exercise increased the degree of eEF2 phosphorylation about twofold (P < 0.05), and values returned to baseline within the 4 h recovery period in each group. However, in the posttest dephosphorylation of eEF2 was negated after recovery in CHO, but not in F. Independent of the dietary condition training
enhanced the basal phosphorylation status of Phospholamban at Thr17, 5′-AMP-activated protein kinase α (AMPKα), and Acetyl CoA carboxylase β (ACCβ), and abolished the exercise-induced increase
of AMPKα and ACCβ (P < 0.05). In conclusion, training in the fasted state, compared with identical training with ample carbohydrate intake, facilitates
post-exercise dephosphorylation of eEF2. This may contribute to rapid re-activation of muscle protein translation following
endurance exercise. 相似文献
13.
Piia Kaikkonen Esa Hynynen Theresa Mann Heikki Rusko Ari Nummela 《European journal of applied physiology》2010,108(3):435-442
The overload principle of training states that training load (TL) must be sufficient to threaten the homeostasis of cells,
tissues, organs, and/or body. However, there is no “golden standard” for TL measurement. The aim of this study was to examine
if any post-exercise heart rate variability (HRV) indices could be used to evaluate TL in exercises with different intensities
and durations. Thirteen endurance-trained males (35 ± 5 year) performed MODE (moderate intensity, 3 km at 60% of the maximal
velocity of the graded maximal test (vVO2max)), HI (high intensity, 3 km at 85% vVO2max), and PRO (prolonged, 14 km at 60% vVO2max) exercises on a treadmill. HRV was analyzed with short-time Fourier-transform method during rest, exercise, and 15-min recovery.
Rating of perceived exertion (RPE), blood lactate (BLa), and HFP120 (mean of 0–120 s post-exercise) described TL of these exercises similarly, being different for HI (P < 0.05) and PRO (P < 0.05) when compared with MODE. RPE and BLa also correlated negatively with HFP120 (r = −0.604, −0.401), LFP120 (−0.634, −0.601), and TP120 (−0.691, −0.569). HRV recovery dynamics were similar after each exercise, but the level of HRV was lower after HI than MODE.
Increased intensity or duration of exercise decreased immediate HRV recovery, suggesting that post-exercise HRV may enable
an objective evaluation of TL in field conditions. The first 2-min recovery seems to give enough information on HRV recovery
for evaluating TL. 相似文献
14.
The use of magnetic resonance imaging to evaluate the effects of cooling on skeletal muscle after strenuous exercise 总被引:1,自引:0,他引:1
Yanagisawa O Niitsu M Yoshioka H Goto K Kudo H Itai Y 《European journal of applied physiology》2003,89(1):53-62
The purpose of this study was to investigate the separate effects of cooling during the acute (within 60 min post-exercise)
or subacute (24–168 h post-exercise) phase on skeletal muscle after exercise. Twenty-eight male subjects [mean (SD) 23.8 (1.8) years]
were randomly assigned to the control (COTG, n=10), cold-water immersion (CWIG, n=9), and double-cold-water immersion groups (DCWIG, n=9). The cold-water immersion (15 min) was administered to the subjects' legs after calf-raise exercise (CWIG: after recording
initial post-exercise measures, DCWIG: after recording initial and 24 h post-exercise measures). Magnetic resonance T2-weighted
images were obtained to calculate the T2 relaxation time (T2) of the triceps surae muscle before, immediately after, and at
the following times post-exercise: 20, 40, and 60 min, and 24, 48, 96 and 168 h. In addition, the ankle joint range of motion,
serum creatine kinase and lactate dehydrogenase, and muscle soreness level were investigated before and after exercise. In
all groups, significant T2 elevations in the gastrocnemius muscle appeared from immediately after to 60 min after exercise
(P<0.05). Thereafter, COTG showed significantly re-elevated T2 levels in the gastrocnemius at 96–168 h post-exercise (P<0.05), while CWIG and DCWIG showed significantly smaller T2 values than the COTG at 96 h post-exercise (P<0.05). In addition, COTG showed larger increases in serum enzymes at 96 h post-exercise (not significant) and significantly
greater muscle soreness levels at 48 h post-exercise (P<0.05) than the cooling groups. The results of this study may suggest that cooling has no dramatic effect, but some minor
effects on reducing exercise-induced muscle edema in the subacute phase and relieving the extent of the damaged muscle cells.
Electronic Publication 相似文献
15.
Benefits of training at moderate altitude versus sea level training in amateur runners 总被引:4,自引:0,他引:4
M. Burtscher W. Nachbauer P. Baumgartl M. Philadelphy 《European journal of applied physiology》1996,74(6):558-563
After more than 25 years of research on altitude training (AT) there is no consensus regarding either the training programme
at altitude or the effects of AT on performance at sea level. Based on a review of the research work on AT, we investigated
combined base training and interval training at moderate altitude and compared immediate and delayed effects on sea level
performance with those following similar sea level training (SLT). The altitude group (AG, 10 male amateur runners) trained
at 2315 m (natural altitude) and the sea level group (SLG, 12 male amateur runners) at 187 m. Both groups performed 7 days
of base training (running on a trail) lasting between 60 and 90 min a day and 5 days of interval training (speed and hill
runs) for between 10 and 45 min a day. Incremental exercise tests were performed 1 week before (t
1), 3 days after (t
2) and 16 days after (t
3) the 12-day main training period. Within AG, exercise performance improved fromt
1 tot
2 by 8% (P<0.05) and fromt
2 tot
3 by 8% (P<0.05). Maximum oxygen uptake (
) increased fromt
2 tot
3 by 10% (P<0.05). Within SLG exercise performance increased fromt
2 tot
3 by 8% (P<0.05). Att
3, relative and absolute
in AG were significantly higher in comparison with SLG (P=0.005 andP=0.046 respectively). The improved performance 3 days after AT may be explained in part by an increased oxygen uptake at submaximal
exercise intensities without a change in
. Further enhancement in performance 2 weeks after AT, however, seems to have been due to the clearly enhanced
. Progressive cardiovascular adjustments might have contributed primarily to the time-dependent improvements observed after
AT, possibly by an enhanced stroke volume overcompensating the reduced heart rates during submaximal exercise. In conclusion,
our findings would suggest that training at a moderate natural altitude improves performance at sea level more than SLT. Combining
base and interval training with regulation of intensity by training at constant heart rates during acclimatization at altitude
would seem to be a successful training regimen for amateur runners. Most beneficial effects became apparent during the subsequent
SLT around 2 weeks after return from altitude. Therefore, we are convinced that AT should be reconsidered as a potent tool
for enhancing aerobic capacity, at least in non-elite athletes. 相似文献
16.
Djalma R. Ricardo Bruno M. Silva Lauro C. Vianna Claudio Gil S. Araújo 《European journal of applied physiology》2010,110(5):933-942
It is not known whether subjects that have higher cardiac vagal reactivation (CVR) during repeated exercise transitions also
have higher cardiac vagal withdrawal (CVW) at the onset of exercise, which would lead to better heart rate (HR) regulation
during exercise transitions. Therefore, our aims were to investigate: (a) the influence of CVR on CVW during repeated rest–exercise
transitions; and (b) the influence of the sympathetic activity on CVR and CVW. Fifty-eight healthy men (22 ± 4 years) performed
20 rest–exercise transitions interspaced by 30 s. In addition, nine healthy men (24 ± 3 years) ingested either 25 mg of atenolol
or placebo, on a crossover, double-blind, randomized design, then performed 20 rest–exercise transitions interspaced by 30 s.
Cardiac vagal reactivation was assessed by a HR variability index (RMSSD) and CVW by the HR increase at the onset of a valid
and reliable cycling protocol. The CVR and CVW responses were associated (partial r ranged from 0.60 to 0.66; p < 0.05). Participants with higher CVR over transitions maintained their CVW over repeated transitions [first transition (mean ± SEM) = 1.59 ± 0.04
vs. 20th = 1.50 ± 0.03 (a.u.), p = 0.24], while participants with lower CVR had a CVW decrease over repeated transitions [first transition (mean ± SEM) = 1.38 ± 0.04
vs. 20th = 1.19 ± 0.03 (a.u.), p < 0.01). In addition, the CVR and CVW over the rest–exercise transitions were similar during atenolol and placebo (ANCOVA
interaction p = 0.12 and p = 0.48, respectively). In conclusion, the CVR among repeated rest–exercise transitions influenced the CVW at the onset of
exercise, which was not affected by a partial β1 cardioselective adrenoceptor blockade. 相似文献
17.
Hani Al Haddad Paul B. Laursen Said Ahmaidi Martin Buchheit 《European journal of applied physiology》2010,108(3):599-606
The aim of the present study was to investigate the effect of cold water face immersion on post-exercise parasympathetic reactivation,
inferred from heart rate (HR) recovery (HRR) and HR variability (HRV) indices. Thirteen men performed, on two different occasions,
an intermittent exercise (i.e., an all-out 30-s Wingate test followed by a 5-min run at 45% of the speed reached at the end
of the 30–15 Intermittent Fitness test, interspersed with 5 min of seated recovery), randomly followed by 5 min of passive
(seated) recovery with either cold water face immersion (CWFI) or control (CON). HR was recorded beat-to-beat and vagal-related
HRV indices (i.e., natural logarithm of the high-frequency band, LnHF, and natural logarithm of the square root of the mean
sum of squared differences between adjacent normal R–R intervals, Ln rMSSD) and HRR (e.g., heart beats recovered in the first
minute after exercise cessation) were calculated for both recovery conditions. Parasympathetic reactivation was faster for
the CWFI condition, as indicated by higher LnHF (P = 0.004), Ln rMSSD (P = 0.026) and HRR (P = 0.002) values for the CWFI compared with the CON condition. Cold water face immersion appears to be a simple and efficient
means of immediately accelerating post-exercise parasympathetic reactivation. 相似文献
18.
In this study we investigated force loss and recovery after eccentric exercise, and further characterized profound losses
in muscle function (n=192 subjects – 98 males, 94 females; population A). Maximal voluntary contractile force (MVC) was assessed before, immediately
after, and at 36 and 132 h after eccentric exercise. Two groups were then established (A1 and A2). Group A1 demonstrated a >70% reduction in MVC immediately after exercise, but were recovering at 132 h after exercise. These subjects
performed a follow-up MVC 26 days later (n=32). Group A2 demonstrated a >70% reduction in MVC immediately post-exercise, but still exhibited a >65% reduction in force at 132 h post-exercise;
these subjects also performed a follow-up MVC every 7 days until full recovery was established (n=9). In population A, there was a 57% reduction in MVC immediately post-exercise and a 67% recovery by 132 h post-exercise
(P < 0.01), with no significant gender differences (P > 0.05). In group A1, although more females (two-thirds) showed large force losses after exercise, these females demonstrated greater %MVC recovery
at 132 h post-exercise (59% vs 44%) and at 26 days post-exercise (93% vs 81%) compared to the males. In group A2, MVC recovery occurred between 33 and 47 days post-exercise. In conclusion, 21% of all subjects showed a delayed recovery
in MVC after high-force eccentric exercise. Although there were no significant gender differences in force loss, a disproportionately
larger number of females demonstrated force reductions of >70%. However, their recovery of force was more rapid than that
observed for the males who also demonstrated a >70% force loss.
Accepted: 2 October 2000 相似文献
19.
20.
Plasma catecholamine responses and neural adaptation during short-term resistance training 总被引:1,自引:0,他引:1
Low exercise-induced plasma adrenaline (A) responses have been reported in resistance-trained individuals. In the study reported
here, we investigated the interaction between strength gain and neural adaptation of the muscles, and the plasma A response
in eight healthy men during a short-term resistance-training period. The subjects performed 5 resistance exercises (E1–E5),
consisting of 6 sets of 12 bilateral leg extensions performed at a 50% load, and with 2 days rest in between. Average electromyographic
(EMG) signal amplitude was recorded before and after the exercises, from the knee extensor muscles in isometric maximal voluntary
contraction (MVC) as well as during the exercises (aEMGmax and aEMGexerc, respectively). Total oxygen consumed during the exercises (V˙O2tot) was also measured. All of the exercises were exhaustive and caused significant decreases in MVC (34–36%, P < 0.001). As expected, the concentric one-repetition maximum (1-RM), MVC and aEMGmax were all higher before the last exercise (E5) than before the first exercise (E1; 7, 9 and 19%, respectively, P < 0.05). In addition, in E5 the aEMGexerc:load and V˙O2tot:load ratios were lower than in E1 (−5 and −14%, P < 0.05), indicating enhanced efficiency of the muscle contractions, However, the post-exercise plasma noradrenaline (NA)
and A were not different in these two exercises [mean (SD) 10.2 (3.8) nmol · l−1 vs 11.3 (6.0) nmol · l−1, ns, and 1.2 (1.0) nmol · l−1 vs 1.9 (1.1) nmol · l−1, ns, respectively]. However, although NA increased similarly in every exercise (P < 0.01), the increase in A reached the level of statistical significance only in E1 (P < 0.05). The post-exercise A was also already lower in E2 [0.7 (0.7) nmol · l−1, P < 0.05) than in E1, despite the higher post-exercise blood lactate concentration than in the other exercises [9.4 (1.1) mmol · l−1, P < 0.05]. Thus, the results suggest that the observed attenuation in the A response can not be explained by reduced exercise-induced
strain due to the strength gain and neural adaptation of the muscles. Correlation analysis actually revealed that those individuals
who had the highest strength gain during the training period even tended to have an increased post-exercise A concentration
in the last exercise as compared to first one (r=0.76, P < 0.05).
Accepted: 10 February 2000 相似文献