Effects of a supervised exercise program on the physical fitness and immunological function of HIV-infected patients.

AIM: Exercise effects in subjects with HIV/AIDS are not entirely understood. The study aimed to investigate the effects of a supervised exercise program on the physical fitness and immunological function of HIV-infected subjects. METHODS: Twenty-seven highly active antiretroviral therapy treated HIV-infected patients (age: 45±2 years; CD4-T: 21.3±2.2%) were assigned to a control (CG, n=8) or experimental (EG, n=19) group. The EG participated in a 12-week exercise program, consisting of aerobic training, strength, and flexibility exercises (3 times/wk; aerobic-30min: PWC 150; strength-50min: 3 sets of 12 reps of 5 exercises at 60-80% 12 RM; flexibility-10min: 2 sets of 30 s at maximal range of motion of 8 exercises). RESULTS: Prior to training there was no significant difference in any variable between the EG and the CG. Flexibility (23%, P<0.05), 12 repetition maximum in the leg press and seated bilateral row exercises (54% and 65% respectively, P<0.05) increased, while the heart rate at a given cycle ergometer workload declined (19% for slope and 12% for intercept, P<0.05) in the EG, but not in the CG. No significant differences were found for the relative and absolute CD4 T-cell counts between groups prior to or after training, but there was a slight enhancement trend in the EG (16%, P=0.19). CONCLUSION: Overall training can improve the muscle and aerobic fitness of HIV-infected patients with no negative effect on their immunological function.

Effects of resistance training on cytokines.

It is speculated that exercise training decreases resting levels of tumor necrosis factor alpha (TNF-alpha) and C-reactive protein (CRP); reduces body mass and leptin (LP); and increases adiponectin (AD) and insulin sensitivity. This systematic review analyzed the effectiveness of resistance training (RT) longitudinal clinical studies on AD, LP, CRP and TNF-alpha. Seventeen studies were included and the majority of randomized controlled trials support that RT produces increases in AD, and decreases in both LP and CRP. Greater responses in AD and LP were evident in overweight and obese individuals; while RT appeared to be effective in reducing CRP in obese individuals, and older adults. Additionally, women may be more responsive to RT effects on AD, LP and CRP. Training duration and intensity may affect the response of AD and CRP with greater responses shown with 16 weeks or more of training and/or with intensities greater than 80% of one repetition maximum. No response to RT of TNF-alpha levels was apparent. Although based on a limited number of studies, some of which are uncontrolled non-randomized in design, our review suggests some positive effects of RT programs on cytokine levels, but specifics of the responses in different populations need further elucidation.

Plasma volume during weight lifting.

The magnitude and pattern of the hematocrit (Hct), hemoglobin (Hb), and plasma volume (PV) responses during and upon recovery from two resistance training protocols based on either a ten-repetition maximum (10 RM) or five-repetition maximum (5 RM) resistance was examined. Twelve college-aged male resistance exercise trainers were equally divided between the protocols and performed at least four workouts prior to testing to determine the 10 RM or 5 RM for each exercise set. Each protocol included three sets of nine exercises. The 10-RM session used one-minute rest periods between sets, and two minutes between exercises. The 5-RM session employed three-minute rest periods between sets and exercises. A catheter inserted in the forearm allowed for venous blood sampling after twenty minutes supine rest, the last set of each exercise, and at fifteen and thirty minutes of recovery. Control conditions were included for posture (P) and limb motion (U). Loaded exercise (L) was significantly different from U and P controls for Hct, Hb, and PV responses. For 10 RM and 5 RM respectively, the mean change from rest was 6.2 (+/- 0.9) and 3.5 (+/- 0.4) % for Hct, 2.2 (+/- 0.2) and 1.2 (+/- 0.1) gm . dl (-1) for Hb, and - 22.6 (+/- 2.3) and - 13.0 (+/- 1.2) % for PV. The main effect for protocol was significant for Hct (p = 0.0006) and Hb (p = 0.0033), with 10-RM changes being greater than 5 RM. The greatest increase in Hct and Hb occurred after the first set for both protocols. An increase in Hct and Hb during the protocol was observed for the 10 RM, but not the 5 RM. During recovery, Hct and Hb were elevated above rest for 10 RM, but not 5 RM. PV decreases mirrored Hct and Hb in pattern of change and significance. The data demonstrate that magnitude and pattern of Hct, Hb, and PV was dependent on the type of resistance training protocol.

Effects of detraining on the functional capacity of previously trained breast cancer survivors.

The purpose of this study was to assess the effects of a relatively short (8-weeks) period of detraining on cardiorespiratory capacity, dynamic strength endurance, task specific functional muscle capacity and quality of life (QOL) of breast cancer survivors who had previously undergone a combined supervised (aerobic and resistance) training program. Eleven women survivors of stage I - II ductal breast carcinoma (47 +/- 7 yrs) entered the study and performed a battery of tests (including anthropometric evaluation, a graded cycle ergometer test, tests of strength endurance [leg and bench press] and the sit-stand test) and completed a specific QOL questionnaire (EORTC-C30) at three time points: i) before, ii) after an exercise program (including aerobic and resistance exercises) of 8-weeks duration, and iii) after a subsequent 8-weeks period of training cessation. Training-induced improvements in strength endurance, muscle functional capacity (sit-stand test) and QOL were not significantly changed after detraining (p > 0.05 for post-training vs. detraining comparisons). The lack of significant loss in muscle strength endurance occurred despite significant losses in estimated total muscle mass after detraining (27.3 +/- 2.4 kg) compared with post-training (28.5 +/- 2.9 kg). In contrast, cardiorespiratory capacity was significantly decreased during detraining (V.O (2peak) of 29.0 +/- 4.6 vs. 22.7 +/- 3.9 ml . kg ( -1) . min (-1) at post-training vs. detraining, p < 0.01). In conclusion, cancer survivors who have participated in a combined training program can retain some of the training gains (particularly improved QOL and muscle strength endurance/functional performance) after a relatively short duration detraining period.

Exercise capacity in a 78 year old patient with McArdle's disease: it is never too late to start exercising.

The case is reported of a 78 year old man with McArdle's disease and a history of treated coronary heart disease. Despite the pre-exercise administration of sucrose allowing the patient to exercise with normal physiological responses, and without typical McArdle's symptoms or biochemical evidence of muscle damage, his exercise capacity was very low (V(O2)peak = 10.7 ml/min/kg), probably attributable to his lifetime of sedentary living. The data suggest that, with pre-exercise sucrose administration, such patients may be candidates for systematic reconditioning, which may improve functional capacity and quality of life.

Combined aerobic and resistance training in breast cancer survivors: A randomized, controlled pilot trial.

The purpose of this pilot study was to examine the effects of a combined cardiorespiratory and resistance exercise training program of short duration on the cardiorespiratory fitness, strength endurance, task specific functional muscle capacity, body composition and quality of life (QOL) in women breast cancer survivors. Sixteen subjects were randomly assigned to either a training (n = 8; age: 50 +/- 5 yrs) or control non-exercising group (n = 8; age: 51 +/- 10 yrs). The training group followed an 8-week exercise program consisting of 3 weekly sessions of 90-min duration, supervised by an experienced investigator and divided into resistance exercises and aerobic training. Before and after the intervention period, all of the subjects performed a cardiorespiratory test to measure peak oxygen uptake (VO2peak), a dynamic strength endurance test (maximum number of repetitions for chest and leg press exercise at 30 - 35 % and 100 - 110 % of body mass, respectively) and a sit-stand test. Quality of life was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 (EORTC-C30) questionnaire. In response to training, QOL, VO2peak (mean 3.9 ml/kg/min; 95 % CI, 0.93, 6.90) performance in leg press (17.9 kg; 95 % CI, 12.8, 22.4) and sit-stand test (- 0.67 s; 95 % CI, - 0.52, - 1.2) improved (p < or = 0.05). We observed no significant changes in the control group. Combined cardiorespiratory and resistance training, even of very brief duration, improves the QOL and the overall physical fitness of women breast cancer survivors.

A method to study lumbar spine response to axial compression during magnetic resonance imaging: technical note.

STUDY DESIGN: A magnetic resonance imaging (MRI)-compatible device was developed to apply calibrated compression loads to the lumbar spine during imaging. Experiments were performed to establish a protocol to measure lumbar load-response and estimate muscle-force contribution to spinal load. OBJECTIVE: To develop experimental methodology for direct study of lumbar spine response to compression load. SUMMARY OF BACKGROUND DATA: Most lumbar MRI scans require subjects to lie relaxed and supine, but spinal stenosis has been demonstrated to increase during moderate compressive loading. Several devices have been used to load the spine during MRI, but they could not maintain and/or change calibrated loads during MRI experiments. Furthermore, artifact from viscoelastic creep during imaging was not considered. METHODS: An MRI-compatible spine compression unit with pneumatic load elements was developed to produce calibrated compression loads. Young healthy men were loaded with 140% body weight for up to 10 minutes to establish an appropriate test protocol. Muscle force contribution to spinal load was estimated from electromyography experiments. RESULTS: The spine compression unit produced specified loads +/- 29 N (standard deviation). Spine viscoelastic creep reached steady state by 6.5 minutes, leaving 3.5 minutes for image acquisition. The subjects could support 1.0 body weight for the requisite 10 minutes. Muscle compressive force estimates were only 135 N during application of 1.4 x body weight external compression load; thus, internal muscle forces during supine spine compression could be neglected. CONCLUSIONS: The lumbar load/image protocol fits within the time constraints of creep deformation and subject endurance. These methods allow acute lumbar mechanical response measurements during loading.

Physiological and performance responses to tournament wrestling.

PURPOSE: The purpose of this study was to investigate the physiological and performance responses to a simulated freestyle wrestling tournament after typical weight loss techniques used by amateur wrestlers. METHODS: Twelve Division I collegiate wrestlers (mean +/- SD;19.33 +/- 1.16 yr) lost 6% of total body weight during the week before a simulated, 2-d freestyle wrestling tournament. A battery of tests was performed at baseline and before and immediately after each individual match of the tournament. The test battery included assessment for body composition, reaction/movement time, lower and upper body power and isokinetic strength, and a venous blood sample. RESULTS: Lower body power and upper body isometric strength were significantly reduced as the tournament progressed (P < or = 0.05). Significant elevations in testosterone, cortisol, and lactate were observed after each match (P < or = 0.05). However, there was a significant reduction (P < or = 0.05) in resting testosterone values in the later matches. Norepinephrine increased significantly (P < or = 0.05) after each match, whereas epinephrine increased significantly (P < or = 0.05) after each match except the last match of each day. Plasma osmolality was consistently higher than normal values at all times including baseline, with significant increases observed after each match (P < or = 0.05). CONCLUSIONS: Tournament wrestling augments the physiological and performance decrements of weight loss and its impact is progressive over 2 d of competition. The combined effects of these stresses may ultimately be reflected in a wrestler's ability to maintain physical performance throughout a tournament.

Effect of resistance training on women's strength/power and occupational performances.

PURPOSE: The effects of resistance training programs on strength, power, and military occupational task performances in women were examined. METHODS: Untrained women aged (mean +/- SD) 23 +/- 4 yr were matched and randomly placed in total- (TP, N = 17 and TH, N = 18) or upper-body resistance training (UP, N = 18 and UH, N = 15), field (FLD, N = 14), or aerobic training groups (AER, N = 11). Two periodized resistance training programs (with supplemental aerobic training) emphasized explosive exercise movements using 3- to 8-RM training loads (TP, UP), whereas the other two emphasized slower exercise movements using 8- to 12-RM loads (TH, UH). The FLD group performed plyometric and partner exercises. Subjects were tested for body composition, strength, power, endurance, maximal and repetitive box lift, 2-mile loaded run, and U.S. Army Physical Fitness Tests before (T0) and after 3 (T3) and 6 months of training (T6). For comparison, untrained men (N = 100) (MEN) were tested once. RESULTS: Specific training programs resulted in significant increases in body mass (TP), 1-RM squat (TP, TH, FLD), bench press (all except AER), high pull (TP), squat jump (TP, TH, FLD), bench throw (all except AER), squat endurance (all except AER), 1-RM box lift (all except aerobic), repetitive box lift (all), push-ups (all except AER), sit-ups (all except AER), and 2-mile run (all). CONCLUSIONS: Strength training improved physical performances of women over 6 months and adaptations in strength, power, and endurance were specific to the subtle differences (e.g., exercise choice and speeds of exercise movement) in the resistance training programs (strength/power vs strength/hypertrophy). Upper- and total-body resistance training resulted in similar improvements in occupational task performances, especially in tasks that involved upper-body musculature. Finally, gender differences in physical performance measures were reduced after resistance training in women, which underscores the importance of such training for physically demanding occupations.

Low-volume circuit versus high-volume periodized resistance training in women.

PURPOSE: The purpose of this investigation was to determine the long-term training adaptations associated with low-volume circuit-type versus periodized high-volume resistance training programs in women. METHODS: 34 healthy, untrained women were randomly placed into one of the following groups: low-volume, single-set circuit (SSC; N = 12); periodized high-volume multiple-set (MS; N = 12); or nonexercising control (CON) group (N = 10). The SSC group performed one set of 8-12 repetitions to muscular failure 3 d x wk(-1). The MS group performed two to four sets of 3-15 repetitions with periodized volume and intensity 4 d x wk(-1). Muscular strength, power, speed, endurance, anthropometry, and resting hormonal concentrations were determined pretraining (T1), after 12 wk (T2), and after 24 wk of training (T3). RESULTS: 1-RM bench press and leg press, and upper and lower body local muscular endurance increased significantly (P < or = 0.05) at T2 for both groups, but only MS showed a significant increase at T3. Muscular power and speed increased significantly at T2 and T3 only for MS. Increases in testosterone were observed for both groups at T2 but only MS showed a significant increase at T3. Cortisol decreased from T1 to T2 and from T2 to T3 in MS. Insulin-like growth factor-1 increased significantly at T3 for SSC and at T2 and T3 for MS. No changes were observed for growth hormone in any of the training groups. CONCLUSION: Significant improvements in muscular performance may be attained with either a low-volume single-set program or a high-volume, periodized multiple-set program during the first 12 wk of training in untrained women. However, dramatically different training adaptations are associated with specific domains of training program design which contrast in speed of movement, exercise choices and use of variation (periodization) in the intensity and volume of exercise.

Testosterone responses after resistance exercise in women: influence of regional fat distribution.

Regional fat distribution (RFD) has been associated with metabolic derangements in populations with obesity. For example, upper body fat patterning is associated with higher levels of free testosterone (FT) and lower levels of sex-hormone binding globulin (SHBG). We sought to determine the extent to which this relationship was true in a healthy (i.e., non-obese) female population and whether RFD influenced androgen responses to resistance exercise. This study examined the effects of RFD on total testosterone (TT), FT, and SHBG responses to an acute resistance exercise test (ARET) among 47 women (22+/-3 years; 165+/-6 cm; 62+/-8 kg; 25+/-5%BF; 23+/-3 BMI). RFD was characterized by 3 separate indices: waist-to-hip ratio (WHR), ratio of upper arm fat to mid-thigh fat assessed with magnetic resonance imaging (MRI ratio), and ratio of subscapular to triceps ratio (SB/TRi ratio). Skinfolds were measured for the triceps, chest, subscapular, mid-axillary, suprailaic, abdomen, and thigh regions. The ARET consisted of 6 sets of 10 RM squats separated by 2-min rest periods. Blood was obtained pre- and post- ARET. TT, FT, and SHBG concentrations were determined by radioimmunoassay. Subjects were divided into tertiles from the indices of RFD, and statistical analyses were performed by an ANOVA with repeated measures (RFD and exercise as main effects). Significant (p < or = .05) increases following the AHRET were observed for TT (approximately 25%), FT (approximately 25%), and SHBG (4%). With multiple regression analysis, anthropometric measures significantly predicted pre- concentrations of FT, post-concentrations of TT, and pre-concentrations of SHBG. The SB/TRi and MRI ratios but not the WHR, were discriminant for hormonal concentrations among the tertiles. In young, healthy women, resistance exercise can induce transient increases in testosterone, and anthropometric markers of adiposity correlate with testosterone concentrations.

Influence of resistance training volume and periodization on physiological and performance adaptations in collegiate women tennis players.

Few data exist on the long-term adaptations to heavy resistance training in women. The purpose of this investigation was to examine the effect of volume of resistance exercise on the development of physical performance abilities in competitive, collegiate women tennis players. Twenty-four tennis players were matched for tennis ability and randomly placed into one of three groups: a no resistance exercise control group, a periodized multiple-set resistance training group, or a single-set circuit resistance training group. No significant changes in body mass were observed in any of the groups throughout the entire training period. However, significant increases in fat-free mass and decreases in percent body fat were observed in the periodized training group after 4, 6, and 9 months of training. A significant increase in power output was observed after 9 months of training in the periodized training group only. One-repetition maximum strength for the bench press, free-weight shoulder press, and leg press increased significantly after 4, 6, and 9 months of training in the periodized training group, whereas the single-set circuit group increased only after 4 months of training. Significant increases in serve velocity were observed after 4 and 9 months of training in the periodized training group, whereas no significant changes were observed in the single-set circuit group. These data demonstrate that sport-specific resistance training using a periodized multiple-set training method is superior to low-volume single-set resistance exercise protocols in the development of physical abilities in competitive, collegiate women tennis players.

The influence of direct supervision of resistance training on strength performance.

PURPOSE: The purpose of this study was to compare changes in maximal strength, power, and muscular endurance after 12 wk of periodized heavy-resistance training directly supervised by a personal trainer (SUP) versus unsupervised training (UNSUP). METHODS: Twenty moderately trained men aged 24.6 +/- 1.0 yr (mean +/- SE) were randomly assigned to either the SUP group (N = 10) or the UNSUP group (N = 8). Both groups performed identical linear periodized resistance training programs consisting of preparatory (10-12 repetitions maximum (RM)), hypertrophy (8 to 10-RM), strength (5 to 8-RM), and peaking phases (3 to 6-RM) using free-weight and variable-resistance machine exercises. Subjects were tested for maximal squat and bench press strength (1-RM), squat jump power output, bench press muscular endurance, and body composition at week 0 and after 12 wk of training. RESULTS: Mean training loads (kg per set) per week were significantly (P < 0.05) greater in the SUP group than the UNSUP group at weeks 7 through 11 for the squat, and weeks 3 and 7 through 12 for the bench press exercises. The rates of increase (slope) of squat and bench press kg per set were significantly greater in the SUP group. Maximal squat and bench press strength were significantly greater at week 12 in the SUP group. Squat and bench press 1-RM, and mean and peak power output increased significantly after training in both groups. Relative local muscular endurance (80% of 1-RM) was not compromised in either group despite significantly greater loads utilized in bench press muscular endurance testing after training. Body mass, fat mass, and fat-free mass increased significantly after training in the SUP group. CONCLUSION: Directly supervised, heavy-resistance training in moderately trained men resulted in a greater rate of training load increase and magnitude which resulted in greater maximal strength gains compared with unsupervised training.

Effects of heavy-resistance training on hormonal response patterns in younger vs. older men.

To examine the adaptations of the endocrine system to heavy-resistance training in younger vs. older men, two groups of men (30 and 62 yr old) participated in a 10-wk periodized strength-power training program. Blood was obtained before, immediately after, and 5, 15, and 30 min after exercise at rest before and after training and at rest at -3, 0, 6, and 10 wk for analysis of total testosterone, free testosterone, cortisol, growth hormone, lactate, and ACTH analysis. Resting values for insulin-like growth factor (IGF)-I and IGF-binding protein-3 were determined before and after training. A heavy-resistance exercise test was used to evaluate the exercise-induced responses (4 sets of 10-repetition maximum squats with 90 s of rest between sets). Squat strength and thigh muscle cross-sectional area increased for both groups. The younger group demonstrated higher total and free testosterone and IGF-I than the older men, training-induced increases in free testosterone at rest and with exercise, and increases in resting IGF-binding protein-3. With training the older group demonstrated a significant increase in total testosterone in response to exercise stress along with significant decreases in resting cortisol. These data indicate that older men do respond with an enhanced hormonal profile in the early phase of a resistance training program, but the response is different from that of younger men.

Acute and chronic hormonal responses to resistance training designed to promote muscle hypertrophy.

Acute and chronic hormonal responses to resistance training were evaluated in 11 college men who completed 12 weeks (33 sessions) of high volume resistance training. No differences in resting concentrations of growth hormone (GH), insulin-like growth factor-I, testosterone, or sex hormone-binding globulin occurred from pre- and posttraining in the trained vs. nontrained control group. However, cortisol (c) decreased 17% for both groups (p < 0.05). There were no differences in exercise-induced responses between Sessions 10 and 20, with all hormone concentrations increasing (p < 0.05) from pre- at mid- and post exercise session. However, after correction for plasma volume decreases, only C and GH showed differences, with C increased from mid- to postsession (48% 10th; 49% 20th), and GH increased from pre- at mid- and postsession for both sessions 10 (0.16 +/- 0.42 pre; 4.77 +/- 6.24 mid; 6.26 +/- 5.19 post; microg x L-1) and 20 (0.33 +/- 0.85 pre; 5.42 +/- 9.08 mid; 8.24 +/- 7.61 post; microg x L-1). Significant correlations (p< 0.05) existed only between absolute mean GH increases from presession and the degree of muscle fiber hypertrophy for type I (r = 0.70 mid, 0.74 post) and type II (r = 0.71 post) fibers. In conclusion, resistance training had no effect on resting serum hormone concentrations, whereas similar acute exercise responses occurred between the 10th and 20th training sessions.

Acute hormonal responses to a single bout of heavy resistance exercise in trained power lifters and untrained men.

The purpose of this study was to investigate the acute responses of both stress and fluid regulatory hormones to a single bout of resistance exercise in both trained and untrained men. Seven competitive power lifters (PL) and 12 untrained subjects (UT) performed one set of the leg press exercise to exhaustion at 80% of their respective one-repetition maximum. Blood samples were obtained twice prior to exercise (at P1 and P2), immediately postexercise (IP), and at 5 minutes postexercise (5PE). Compared to P1 and P2, plasma epinephrine, norepinephrine, dopamine, atrial peptide, osmolality, and blood lactic acid increased significantly (p < or = 0.05) at IP. Plasma epinephrine, norepinephrine, atrial peptide, and blood lactic acid concentrations remained elevated at 5PE compared to P1 and P2. Plasma renin activity and angiotensin II were significantly elevated at 5PE compared to P1, P2, and IP, and this increase was significantly greater in PL compared to UT at 5PE. These data indicate that an acute bout of resistance exercise dramatically affects secretion of stress and fluid regulatory hormones.

Sample size required for the accurate determination of fiber area and capillarity of human skeletal muscle.

This study aimed to determine the skeletal muscle fiber sample size required for a reliable, valid representation of an individual's average fiber area and capillary contacts (CC) per fiber. Biopsies were obtained from the biceps brachii of 11 college-age, recreational resistance-trained men in conjunction with a study investigating how muscle morphology changed after 12 weeks of resistance training. The effect of additional measurements on the rolling cumulative means for fiber area and CC per fiber was evaluated using sequential estimation analysis. Results showed that group cumulative mean and standard deviation had stabilized by 50 fiber measurements per individual for type I and II fibers and CC per fiber. Significant correlations (.96-.99; p < .05) existed between the 50th and 95th/100th cumulative individual means. These results indicate that a typical skeletal muscle needle biopsy would be sufficient to characterize type I and II fiber areas and CC per fiber of an individual in most subject populations, although the required sample size for characterizing fiber subtypes might be different.

Acute hormonal responses to heavy resistance exercise in younger and older men.

The purpose of this investigation was to examine the acute responses of several hormones [total and free testosterone (TT and FT, respectively), adrenocorticotropic hormone (ACTH), cortisol (C), growth hormone (GH), and insulin (INS)] to a single bout of heavy resistance exercise (HRE). Eight younger [30-year (30y) group] and nine older [62-year (62y) group] men matched for general physical characteristics and activity levels performed four sets of ten repetitions maximum (RM) squats with 90 s rest between sets. Blood samples were obtained from each subject via an indwelling cannula with a saline lock pre-exercise, immediately post-exercise (IP), and 5, 15 and 30 min post-exercise. Levels of TT, FT, ACTH, C and lactate significantly increased after HRE for both groups. Pre-HRE pairwise differences between groups were noted only for FT, while post-HRE pairwise differences were found for TT, FT, GH, glucose and lactate. Area under the curve analysis showed that the 30y group had a significantly higher magnitude of increase over the entire recovery period (IP, 5, 15, and 30 min post-exercise) for TT, FT, ACTH and GH. Few changes occurred in the INS response with the only change being that the 62y group demonstrated a decrease IP. Lactate remained elevated at 30 min post-HRE. This investigation demonstrates that age-related differences occur in the endocrine response to HRE, and the most striking changes appear evident in the FT response to HRE in physically active young and older men.

The effects of salmeterol on power output in nonasthmatic athletes.

BACKGROUND: Salmeterol xinafoate is a new aerosol inhalant that is used in the treatment of asthma. It is currently banned by the International Olympic Committee because of the concern that it may lend an unfair competitive advantage to the user. OBJECTIVE: The purpose of this study was to determine whether salmeterol improves short-term anaerobic performance in elite nonasthmatic track cyclists. METHODS: Eleven elite track cyclists volunteered to perform a 30-second all-out cycle ergometer test 3 hours after receiving either 42 micrograms of salmeterol xinafoate or placebo applied in a double-blind crossover procedure. During the ergometer test, peak power output, total work, time to peak power, and percent fatigue (decline in power output) were measured. Pulmonary measurements were also taken before and at various time points after inhalation and the ergometer test. A methacholine challenge was administered to each subject before participation in the study to ensure that none of the subjects had any reactive airway diseases. RESULTS: There were no significant differences (p > 0.05) between the placebo and salmeterol trials for peak power output, total work performed during the 30-second test, percent fatigue, and time to peak power. No differences between trials were observed for the pulmonary function test variables at any of the time points. Blood lactate concentrations before and after administration of drug or placebo were also not significantly different between trials. Additionally, salmeterol did not affect the maximal heart rate achieved during the test as compared with the placebo. CONCLUSIONS: Short-term salmeterol use within the prescribed dosage was not shown to increase short-term power output in nonasthmatic cyclists.