1
|
Ramírez-Marrero FA, Smith BA, Sherman WM, Kirby TE. Comparison of Methods to Estimate Physical Activity and Energy Expenditure in African American Children. Int J Sports Med 2005; 26:363-71. [PMID: 15895319 DOI: 10.1055/s-2004-821011] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Low levels of physical activity and high levels of obesity among children in the US is a public health concern. Accurate methods to estimate physical activity are needed to determine the efficacy of intervention programs and to explore relationships between daily physical activity and health status in children. The purpose of this study was to compare the simultaneous use of the Tritrac-R3D accelerometer (Tritrac), Yamax SW-200 Digiwalker step-counter (Digiwalker) and the Self Administered Physical Activity Checklist (SAPAC) to assess physical activity (PA) and energy expenditure (EE) in African-American children aged 7 to 10 years, using the doubly-labeled water (DLW) as the criterion method. Physical activity and energy expenditure were measured over seven consecutive days under free-living conditions. Resting metabolic rate and peak VO(2) were measured before the experimental period. There was no difference in physical activity energy expenditure (PAEE) measured by Tritrac or DLW (p > 0.05). Tritrac activity counts were highly correlated with DLW-PAEE (r = 0.81). High correlations between Digiwalker and DLW were observed when body weight was considered. A low correlation (r = 0.49) was observed between the physical activity energy expenditure by SAPAC and DLW. In conclusion, with some limitations the Tritrac and Digiwalker can provide useful and accurate information about PA and EE in 7- to 10-year-old children.
Collapse
Affiliation(s)
- F A Ramírez-Marrero
- School of Physical Activity and Educational Services, Sport and Exercise Sciences Section, The Ohio State University, Columbus, USA.
| | | | | | | |
Collapse
|
2
|
Abstract
Athletic trainers typically use therapeutic ultrasound to treat skeletal muscle contusion injuries. However, the structural outcomes underlying this treatment are not well understood. Our working hypothesis was that following a blunt contusion injury to the gastrocnemius muscle, ultrasound treatment would facilitate recovery, as indicated by changes in several biological markers of skeletal muscle regeneration. Eighty male Wistar rats (three-month) were studied. Following anesthetic administration, each animal received a bilateral contusion injury to the gastrocnemius muscle. Pulsed ultrasound treatment was subsequently initiated six hours post-contusion injury unilaterally on the right gastrocnemius muscle, and ultrasound treatment was continued once daily for seven days. The left (non-ultrasound treated) and right (ultrasound treated) gastrocnemius muscles of 10 animals per group were excised at 1-, 3-, 5-, 7-, 14-, 21-, 28-, and 40-days post-contusion injury. There were no differences in muscle mass, total protein concentration, or fiber cross-sectional area between the right and left gastrocnemius muscles at any post-injury time point examined. Further, when fiber cross-sectional area was normalized to muscle mass, there were no differences. Myonuclear number and cross-sectional area per myonuclei between the right and left gastrocnemius muscles were not different. These results suggest that ultrasound, as administered, does not hasten or improve the regeneration of skeletal muscle following contusion injury.
Collapse
Affiliation(s)
- L D Wilkin
- Section of Sport and Exercise Sciences, The Ohio State University, 337 West Seventeenth Avenue, Columbus, OH 43210-1284, USA
| | | | | | | |
Collapse
|
3
|
Wallace LS, Buckworth J, Kirby TE, Sherman WM. Characteristics of exercise behavior among college students: application of social cognitive theory to predicting stage of change. Prev Med 2000; 31:494-505. [PMID: 11071829 DOI: 10.1006/pmed.2000.0736] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Young adulthood is characterized by a steep decline in the level of physical activity, but few theory-based studies have examined characteristics associated with regular exercise in this population. This study applied Social Cognitive Theory (SCT) and the Stages of Change Model (SCM) to determine personal, behavioral, and environmental characteristics associated with exercise behavior and intentions among undergraduate university students. METHODS A random sample of 937 undergraduate students (mean age 22.0 +/- 5.6 years; 84.7% ages 17-24 years) enrolled at a large Midwestern university completed a mailed questionnaire. Valid and reliable instruments were used to measure personal, behavioral, and environmental variables based on the SCT that were hypothesized to influence stage of exercise behavior change. Multivariate discriminant analysis was used to determine associations among these variables with stage of exercise behavior change. RESULTS Exercise self-efficacy, physical activity history, and nonexercise estimation of aerobic capacity were significant predictors of the stage of exercise behavior change for both males and females. Among females, exercise self-efficacy (P < 0.001) and family social support (P < 0. 001) for physical activity were the best predictors of stage of exercise behavior change. Friend social support (P < 0.001), physical activity history (P < 0.001), and exercise self-efficacy (P < 0.001) were significant predictors of stage of exercise behavior change among males. CONCLUSIONS The SCT framework predicted stage of exercise behavior change as defined by the SCM. Exercise self-efficacy was associated with exercise stage, but the source of significant social support (family versus friends) was different for males and females.
Collapse
Affiliation(s)
- L S Wallace
- Department of Health and Kinesiology, University of Texas at Tyler, Tyler, Texas 75799, USA.
| | | | | | | |
Collapse
|
4
|
Ferketich AK, Kirby TE, Alway SE. Cardiovascular and muscular adaptations to combined endurance and strength training in elderly women. Acta Physiol Scand 1998; 164:259-67. [PMID: 9853013 DOI: 10.1046/j.1365-201x.1998.00428.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Twenty-one women aged 60-75 years were examined to determine whether combined endurance and strength training resulted in greater increase in peak oxygen consumption, sub-maximal time to fatigue, cardiac output, stroke volume, and leg extension load when compared to endurance training alone. Subjects in both the endurance training (E) and endurance and strength (E & S) groups trained 3 days a week, for 12 weeks, at an intensity of 70-80% Vo2 peak for 30 min on a cycle ergometer. Subjects in the E & S groups also used resistance equipment to train the knee extensors. The workload for resistance training was based on an initial assessment of 10 repetitions maximum (10 RM), with 80% of that value used for training, three times weekly. Peak oxygen consumption increased to an average of 24.8 and 29.9% in the E and E & S groups, respectively, with no difference between groups. Subjects in the E & S and E groups significantly increased sub-maximal endurance time by 396 and 165%, respectively. Cardiac output, stroke volume, and arteriovenous oxygen difference at 80% peak VO2 were unchanged by either of the training methods. A needle biopsy was taken from the vastus lateralis before and after 12 weeks of training. Chi-square analysis of fibre area data showed an increase in the frequency of larger type I fibres in the post-training data from the E & S group, but an increase in the frequency of smaller fibres in the E group post-training; however, mean fibre area was not significantly changed by training. These data suggest that greater improvements in sub-maximal time to fatigue and strength is achieved when resistance training is added to an aerobic training programme in healthy elderly women.
Collapse
Affiliation(s)
- A K Ferketich
- Department of Exercise and Sport Sciences, Ohio State University, Columbus, USA
| | | | | |
Collapse
|
5
|
Sherman WM, Morris DM, Kirby TE, Petosa RA, Smith BA, Frid DJ, Leenders N. Evaluation of a commercial accelerometer (Tritrac-R3 D) to measure energy expenditure during ambulation. Int J Sports Med 1998; 19:43-7. [PMID: 9506799 DOI: 10.1055/s-2007-971878] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This study evaluated the ability of a commercially available accelerometer (Tritrac-R3 D) to measure energy expenditure in 16 subjects at rest (pre- and post-exercise) and during three different intensities of steady-state exercise (40-70% of peak oxygen consumption [VO2peak]) while ambulating on a treadmill (no grade). Oxygen consumption and the respiratory exchange ratio from indirect calorimetry and the vector magnitude of triaxial accelerations were used to estimate energy expenditure using the manufacturers' equations. There was a significant relationship between indirect calorimetry-derived energy expenditure and the energy expenditure derived from the accelerometer (r=0.96). Using analysis of variance, there was no difference in the energy expenditure derived by the two methods at rest before exercise and during the three different intensities of ambulatory exercise. There was a significant difference between energy expenditure derived via indirect calorimetry and with the accelerometer during rest after exercise, probably due to the failure of the accelerometer to accurately estimate the energy expenditure associated with the progressive decline in post-exercise oxygen consumption. Thus, this commercially available accelerometer appears to provide statistically acceptable estimates of energy expenditure at rest and during zero-grade treadmill ambulation up to about 70% VO2peak. This may indicate its acceptable utility for large-scale population studies of physical activity involving this mode of movement. The failure of the accelerometer to accurately estimate energy expenditure during recovery from exercise may contribute to an underestimation of energy expenditure in some physically active individuals.
Collapse
Affiliation(s)
- W M Sherman
- School of Physical Activity and Educational Services, College of Education, The Ohio State University, Columbus 43210, USA
| | | | | | | | | | | | | |
Collapse
|
6
|
Albright AL, Mahan JD, Ward KM, Sherman WM, Roehrig KL, Kirby TE. Diabetic nephropathy in an aerobically trained rat model of diabetes. Med Sci Sports Exerc 1995; 27:1270-7. [PMID: 8531625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The purpose of this study was to determine the effects of aerobic training on indices of glycemic control, blood pressure, serum lipids, and diabetic nephropathy (DN) in an animal model of insulin deficient diabetes mellitus. Thirty-four male Sprague-Dawley rats made diabetic with streptozocin were randomly assigned to a trained group or a sedentary group. Fifteen sedentary-nondiabetic rats served as a control group. The animals were trained on a treadmill at 18 m.min-1, 8 degrees incline for 120 min.d-1, 5 d.wk-1. Blood and 24 h urine collections were obtained at various intervals throughout the study. At 21 wk of age systolic blood pressure was measured and kidney tissue was obtained for light and electron microscopy. Analysis of variance was used to detect differences among the groups (P < or = 0.05). The diabetes produced in this investigation resulted in hyperglycemia, increased urine albumin and total protein excretion, elevated systolic blood pressure, increased fractional volume of the mesangium, and widening of the glomerular basement membrane in the sedentary-diabetic animals. Aerobic training significantly reduced the increase in fractional volume of the mesangium and fructosamine. Most importantly, aerobic training did not augment the renal damage seen in DN.
Collapse
Affiliation(s)
- A L Albright
- School of Health, Physical Education and Recreation, Department of Pediatrics, Ohio State University, Columbus 43210, USA
| | | | | | | | | | | |
Collapse
|
7
|
Rousseau AK, Alway SE, Kirby TE. THE EFFECTS OF COMBINED ENDURANCE AND STRENGTH TRAINING IN WOMEN AGE 60-75. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-01099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
8
|
DeLeon AD, Rousseau AK, Kirby TE, Alway SE. MUSCLE FIBER CHARACTERISTICS AFTER ENDURANCE OR ENDURANCE AND STRENGTH TRAINING IN ELDERLY WOMEN. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-01308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
9
|
Sherman WM, Morris DM, Kirby TE, Petosa R, Smith BA, Frid DJ. VALIDITY OF THE TRITRACR® ACCELEROMETER. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-00428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
10
|
Casenhiser-Sutterluety AJ, Kirby TE, Sherman WM. EFFECTS OF A LOW CALORIE DIET IN COMBINATION WITH RESISTANCE OR AEROBIC TRAINING ON METABOLIC RATE. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-00406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
11
|
Smith BA, Hamlin RL, Bartels RL, Evans RG, Kirby TE, MacVicar MG, Weisbrode SE. Myocardial infarction size and scar dimensions: the influence of activity. Heart Lung 1992; 21:440-7. [PMID: 1399663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE The purpose of this study was to determine myocardial infarct size and scar dimensions in experimentally infarcted rats that were randomly assigned to a moderate, mild, or no exercise condition after infarction. DESIGN Pretest-posttest control group design (experimental). SUBJECTS 57 male Harlan Sprague Dawley rats between 62 to 64 days of age and weighing 220 to 290 gm at the onset of the study. OUTCOME MEASURES Infarction size, scar thickness, thinnest portion of scar. INTERVENTION Mild exercise versus moderate exercise versus no exercise. RESULTS No differences were found in infarct size, scar thickness, or thinnest portion of scar among the three groups. CONCLUSION This study establishes that treadmill exercise, begun after an appropriate period of recovery, does not necessarily increase infarct size or scar thinning in the rat model. Further, animal and human studies are needed to fully explore the benefits and hazards of cardiac rehabilitation or exercise testing before or soon after discharge.
Collapse
Affiliation(s)
- B A Smith
- College of Nursing, The Ohio State University, Columbus 43210
| | | | | | | | | | | | | |
Collapse
|
12
|
Pruitt LA, Sherman UK, Kirby TE, Walsh H, Ferrara C, Jewell-Burke K. AEROBIC FITNESS, PHYSICAL ACTIVITY, AND CARDIOVASCULAR DISEASE RISK FACTORS IN ASTHMATIC AND NONASTHMATIC CHILDREN. Med Sci Sports Exerc 1992. [DOI: 10.1249/00005768-199205001-00205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
13
|
Cunningham KH, Kirby TE, Saith BA, Montelto LN. ST SEGMENT CHANGES DUE TO HANDRAIL SUPPORT DURING GRADED EXERCISE TREADNILL TESTING. Med Sci Sports Exerc 1992. [DOI: 10.1249/00005768-199205001-00677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
14
|
Smith BA, Fetters JL, Kelsy MA, Kirby TE, Cooley SL, Pruitt LA. Exercise and cardiovascular risk in black children. J Hum Hypertens 1990; 4:127-9. [PMID: 2338683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The purposes of this study were to document the prevalence of cardiovascular disease risk factors in twenty black children to compare methods of measurement of blood pressure, body composition, and smoking; and to evaluate the effects of a ten week aerobic exercise training programme on blood pressure, cholesterol, smoking behaviour, and oxygen consumption. At pretest 25% of the children had blood pressures above the 90th percentile for their age or gender, 60% had a total cholesterol above 180 mg/dl and 35% exceeded 28% body fat. The mean difference score between systolic blood pressure and diastolic blood pressure measurements using a standard mercury sphygmomanometer and the Dinamap manometer was 1.5 (P less than 0.01) and 14.9 (P less than 0.0001) respectively. There was no significant difference in any of the methods used to measure body composition. Finally, there was no significant difference between the groups with regard to the dependent variables. Although the investigators identified the presence of elevated blood pressure, elevated total cholesterol, and obesity in this sample, the aerobic exercise training programme did not alter the risk profile. The authors urge caution in interpreting these results. Selection of the method for measurement of BP should be made with caution. A clear understanding of how each instrument works and its precision must be considered. Selection of the method for measurement of body composition can be based upon factors such as availability of equipment, cost, convenience, and subject preference.
Collapse
Affiliation(s)
- B A Smith
- Ohio State University, College of Nursing and School of Health, Physical Education, and Recreation, Columbus 43210
| | | | | | | | | | | |
Collapse
|
15
|
Paul GL, DeLany JP, Snook JT, Seifert JG, Kirby TE. Serum and urinary markers of skeletal muscle tissue damage after weight lifting exercise. Eur J Appl Physiol Occup Physiol 1989; 58:786-90. [PMID: 2737198 DOI: 10.1007/bf00637392] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The purpose of this study was to determine whether high intensity weight lifting exercise produces elevations of urinary 3-methylhistidine (3-MH), serum creatine kinase activity (CK), and serum myoglobin concentration (MY), and whether trained weight lifters differed in such responses when compared to a group of untrained subjects. Ten experienced male weight lifters (EWL) and seven untrained male subjects (IWL) performed three sets of six weight lifting exercises at 70%-80% of 1 RM. All subjects consumed a meat-free diet. The 3-MH:creatinine (3-MH:CR) values decreased 24 h and 48 h following exercise (P less than 0.05). The 12-h and 24-h postexercise CK response and the 12-h postexercise MY response increased for both EWL and IWL (P less than 0.05). However, EWL had a lower 24-h postexercise CK response and lower 12-h and 24-h postexercise MY responses compared to IWL (P less than 0.05). Within 48 h following weight lifting exercise, skeletal muscle protein degradation (as assessed by 3-MH:CR values) decreased regardless of prior training experience whereas skeletal muscle tissue damage (as assessed by CK and MY responses) increased. However, prior weight lifting training appeared to diminish the extent of muscle tissue damage.
Collapse
Affiliation(s)
- G L Paul
- Exercise Physiology Laboratory, Ohio State University, Columbus 43210
| | | | | | | | | |
Collapse
|
16
|
Haffor AS, Bartels RL, Kirby TE, Hamlin RL, Kunz AL. Carbon dioxide storage capacity of endurance and sprint-trained athletes in exercise. Arch Int Physiol Biochim 1987; 95:81-90. [PMID: 2444186 DOI: 10.3109/13813458709104518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The purpose of this study was to compare CO2 storage capacity of endurance and sprint-trained athletes during steady state exercise. Ten subjects, five sprinters and five distance runners, performed a submaximal treadmill exercise at two different work rates, 45% and 65% of VO2max. CO2 storage capacity was determined by measuring the excess CO2 washout associated with hyperventilation, normalized for body weight and expressed per unit change in mixed venous PCO2 (ml kg-1 Torr-1). Mixed venous PCO2 (PvCO2) was measured by rebreathing equilibration. It was found that CO2 storage capacities of the runners were significantly (P less than 0.05) greater than the sprinters at the two work rates. The sprinters CO2 storage capacities were 2.69 and 2.14 ml kg-1 Torr-1 at low and high work rates, respectively. The corresponding mean values for the runners were 4.56 and 3.92 ml kg-1 Torr-1, respectively. These results may be explained by the metabolic differences between the sprinters and runners. The sprinters' musculature depends more heavily on the glycolytic metabolic pathway, which is associated with an increased lactate production and hence a reduction in the combining power of the blood for CO2 during exercise. At the low work rate, the body's storage capacity for CO2 was significantly (P less than 0.05) greater than the higher work rate for both groups. Obviously, at the higher work level more blood would be presented to the lungs per unit time allowing an increase in CO2 clearance from the body stores.
Collapse
Affiliation(s)
- A S Haffor
- Dpt. of HPER, Mississippi State University, MS 39762
| | | | | | | | | |
Collapse
|
17
|
|
18
|
Paul GL, DeLany JP, Snook JT, Kirby TE. THE EFFECTS OF A WEIGHT LIFTING WORKOUT ON SERUM CREATINE KINASE, MYOGLOBIN, AND 3-METHYLHISTIDINE IN EXPERIENCED AND INEXPERIENCED WEIGHT LIFTERS. Med Sci Sports Exerc 1986. [DOI: 10.1249/00005768-198604001-00330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
19
|
Cleary PA, Kirby TE, Shook DS, Fox EL, Bartels RL, Schaal S. THE EFFECT OF PROPRANOLOL ON THE TRAINING RESPONSE TO ENDURANCE EXERCISE IN NORMAL HUMAN ADULTS. Med Sci Sports Exerc 1985. [DOI: 10.1249/00005768-198504000-00260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
20
|
Pratt CM, Welton DE, Squires WG, Kirby TE, Hartung GM, Miller RR. Demonstration of training effect during chronic beta-adrenergic blockade in patients with coronary artery disease. Circulation 1981; 64:1125-9. [PMID: 6117378 DOI: 10.1161/01.cir.64.6.1125] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Attenuation of exercise-induced increases in heart rate and cardiac output by chronic beta-adrenergic blockade has been thought to compromise benefit of exercise training in patients with coronary artery disease (CAD). To assess this important issue, 35 CAD patients were evaluated by a 3-month walk-jog-cycle training program: 14 patients received no beta blocker (group 1), 14 received propranolol, 30-80 mg/day (group 2), and seven patients received propranolol, 120-240 mg/day (group 3). The extent of CAD, resting heart rate before training blood pressure and VO2 max were similar (p = NS) in each group. The maximal exercise heart rate (mean +/- SD, 147 +/- 21 beats/min in group 1 vs 120 +/- 10 beats/min in group 2 and 115 +/- 12 beats/min in group 3 (both p less than 0.05 vs group 1). The VO2 max before training was 25 +/- 5.0 ml/kg/min in group 1 vs 23 +/- 3.2 ml/kg/min in group 2 and 26 +/- 2.8 ml/Kg/min in group 3 (all p = NS). Training consisted of three 1-hour periods per week at a heart rate of 70-85% of the maximal pretraining heart rate. In each group, VO2 increased (p less than 0.05) after training: group 1, 27%; group 2, 30%; group 3, 46%. The double product was unchanged after training (p = NS) in each group. These data indicate that substantial training effects may be achieved in CAD patients despite therapeutic doses of beta blockers and a reduced training HR. Thus, there appears to be no indication to reduce beta blockers in CAD patients engaged in cardiac rehabilitation.
Collapse
|