Ted A. Kaplan

Physical and psychological changes with vigorous exercise in sedentary primigravidae

PURPOSE The present study examined the effects of exercise on physical and psychological variables in sedentary primigravidae (PRA). METHODS A total of nine women randomly assigned to an exercise (E) (mean age = 31.3 +/- 3.1 yr) and six subjects randomly assigned to a control (C) group (mean age = 27.8 +/- 3.1 yr) fulfilled all requirements for the study. Exercise included a variety of exercise activities performed to a target heart rate of 150-156 beats x min(-1), three times per week for 15 wk. RESULTS Results showed no significant differences between E and C groups in physical characteristics initially. A repeated measures ANOVA showed a significant group effect (P < 0.05) and a significant group by time interaction (P = 0.001) with the E group showing a significantly longer amount of time on the PWC150 test than the C group. There was no significant group, time, or group by time interaction for lactate accumulation. This occurred, despite the fact that the E group spent 56% longer on the PWC150 test and the C group spent 30% less time on the same test at the conclusion of the study. Finally, the E group in comparison to the C group showed more favorable improvements in several items related to health and well-being on the Body Cathexis Scale. There were no significant differences between E and C groups in any pregnancy outcome measures. All babies were delivered healthy at term. CONCLUSIONS These data suggest that a vigorous exercise program can lead to significant improvements in aerobic fitness at similar lactate concentrations compared to a control group and can be well tolerated by low risk sedentary PRA without any deleterious effects occurring to herself or unborn child.

Exercise-Induced Bronchospasm in Nonasthmatic Obese Children:

The frequency, degree, and pattern of bronchial reactivity to exercise were compared in 13 obese and 14 control children, ages 6 to 10 years, with no history of asthma. Spirometry was performed before and every three minutes after a seven-minute exercise challenge on a treadmill. There were 11 obese children and 6 controls who had at least a 15% fall in at least one of three monitored pulmonary function parameters (P<.05). The group mean percentage falls in FEV1 and FEF25%-75% were significantly greater in the obese group than in the controls. The pattern of bronchospasm, occurring soon after the exercise challenge, is consistent with that found in the known asthmatic population. A significant correlation was found between triceps skin-fold thickness and degree of fall in FEF25%-75% ( r= .55, P<.005). This study demonstrated that significantly greater frequency and degree of bronchospasm of the smaller airways occur in obese children, partially related to the amount of subcutaneous fat. Whether exercise-induced bronchospasm leads to exercise avoidance and obesity or whether obesity causes or enhances bronchial hyperreactivity to exercise requires further study.

Effects of acute inhalation of the bronchodilator, albuterol, on power output

This study was designed to examine the effects of acute inhalation of the bronchodilator, albuterol (Proventil, Schering Corp.), on high intensity power output. Fifteen healthy nonasthmatic subjects (eight male, seven female, 18-33 yr) performed four supramaximal 15-s rides on a bicycle ergometer. Rides were arranged in pairs with a 10-min rest interval. Each pair of rides was preceded by a 5-min warm-up. Sessions were separated by a minimum of 48 h. The study design was fully randomized and double blind. Ten minutes prior to each pair of rides subjects inhaled two metered doses (180 micrograms) of albuterol (A) or a placebo (P). Individual ANOVAs revealed a significant difference between the A and P treatment for peak power (A = 886.6 W, P = 858.3 W) and fatigue (A = 27.2%, P = 24.4%). Mean changes in FEF25-75% (A = 0.712, P = 0.040 l.s-1), FEV1.0 (A = 0.188, P = 0.007 l), and PEF (A = 0.573, P = -0.155 l.s-1) were also statistically significant; however, these changes did not correlate to the anaerobic performance changes. No significant differences were found between treatments for heart rate increases resulting from the power test (A = 56.73 bpm, P = 53.20 bpm). These results indicate an ergogenic effect of the bronchodilator on short-term power output independent of impact on respiratory smooth muscle, with no effect on cardiac response.

Effect of obesity on injury risk in high school football players

Little is known about the relative injury risk of obese adolescent football players. Two high school varsity teams were followed prospectively for injuries after measurement of height, weight, and triceps and subscapular skinfolds during the preseason. Certified athletic trainers who were present at all practices recorded all injuries that required a player to miss at least one practice or game. In all, 98 players were enrolled in the study. Twenty-eight injuries were documented in 24 different players. There were 27 (28%) players with the sum of skinfolds > or = 95th percentile for age; eight of them had nine injuries. The overall prevalence of injuries per player per season was 0.28 for players < or = 95th percentile and 0.33 for players above this percentile (not significant). High body mass (body weight > 90 kg) was associated with a 2.5 times higher relative risk of injury. While this study did not find evidence for an overall higher injury rate in overly fat high school football players, an alarmingly high incidence of obesity was found in this athletic population.

Impact of CF Summer Camp

In two consecutive years, patients with cystic fibrosis were studied at the beginning and end of a nine-day summer camp program to assess the programs effects on weight gain and pulmonary function. The camp experience includes daily exercise and a high-protein and high-fat diet. There were a total of 58 children between 6 and 12 years of age (42 different patients) and 10 adult counselors from 19 to 30 years of age (eight different patients). On the first and eighth days patients were weighed, sputum cultures were collected, and spirometry was performed. In year 2, peak expiratory flow rate was monitored daily. Also in year 2, campers and counselors with CF were prescreened by sputum culture and excluded from camp if they had Pseudomonas cepacia in their sputum. Only one candidate screened was positive before camp. In year 1, no significant group changes in pulmonary function were identified. In year 2, significant increases on post-camp testing were found for FEF 25%-75% and PEF. Mean body weight for all patients increased significantly, by 0.4 kg in year 1 and 0.9 kg in year 2 (p <. 05) . In year 1, a total of nine patients acquired a new organism in their follow-up sputum culture, including five who acquired a new Pseudomonas species. There was no intra-cabin pattern of spread. Four patients were positive for P. cepacia on day 1 culture. No new subjects acquired this organism on follow-up examination. In year 2, only one subject had P. cepacia on the first camp collection; he alone was positive on day 9. Physiological effects on body weight and pulmonary function varied on an individual basis, revealing significant group benefits in body weight and, in year 2, a reduction of pulmonary obstruction. P. cepacia was not transmitted in this setting, with or without prescreening.

Lack of effect of delta F508 mutation on aerobic capacity in patients with cystic fibrosis.

ObjectiveAs aerobic exercise capacity, as defined by vO2max, is associated with patient functioning and possibly prognosis in cystic fibrosis (CF), correlations between vO2max, phenotype and genotype may be of value. DesignRetrospective clinical series. SettingCystic fibrosis referral clinic. PatientsConvenience sample of 35 patients with CF consecutively referred for exercise testing. Main outcome measuresBlood samples were examined for mutations of cystic fibrosis transmembrane regulator (CFTR). Height, weight, pulmonary function, resting-energy expenditure, vO2max, and other exercise variables were assessed in each referred patient. ResultsStatistical comparison of 10 patients who were homozygous for the dF508 mutation of CFTR with 20 patients heterozygous for dF508 revealed no significant differences for height, weight, pulmonary function, resting-energy expenditure, vO2max, or any other exercise variables. ConclusionsThese results imply a limited effect of the mutation status on overall patient functioning and prognosis. Future identification of more rare CFTR mutations and other genes and subsequent classification of patients in a manner reflective of the cellular physiology may lead to different results.

Obesity in a high school football candidate: a case presentation.

A 14-yr-old male presented for medical clearance to play fall football for his high school team. He had stayed out of the prior spring football practice sessions after a shoulder injury on the first day of practice, but indicated no other positive responses to the standard medical questionnaire. He was severely overweight with height of 180 cm, weight 133.4 kg, and his estimated body fat was 36%. His examination was otherwise not revealing. He demonstrated poor aerobic fitness, exercise-induced bronchospasm, residual left shoulder weakness, and a dyslipoproteinemia on further medical evaluation. He was disqualified on an empirical basis, the attending physician making the clinical decision that it would be of greater harm than good for this adolescent to participate. However, there is little data and no established guidelines for this type of situation. The overweight football athlete is a challenge to the sports medicine team, both in managing the condition and in determining athletic eligibility.