Effects of an Acute Strength and Conditioning Training Session on Dual-Energy X-Ray Absorptiometry Results.

Lytle, JR, Stanelle, ST, Kravits, DM, Ellsworth, RL, Martin, SE, Green, JS, and Crouse, SF. Effects of an acute strength and conditioning training session on dual-energy x-ray absorptiometry results. J Strength Cond Res 34(4): 901-904, 2020-The purpose of this study was to determine whether an athletic strength and conditioning (S&C) session will alter body composition estimates of a dual-energy x-ray absorptiometry (DXA) scan. Twenty-two strength-trained individuals (15 men, 7 women, 24 ± 2 years, 174.2 ± 8.5 cm, 83.5 ± 15.0 kg) volunteered to participate in the study. Each subject underwent 2 DXA scans, before and after completion of the S&C session, which consisted of upper- and lower-body resistance exercises and interval running. Subjects consumed a free-living meal before the first scan, after which only ad libitum water intake was consumed until completing the second scan. Results were analyzed through sex by time repeated-measures analysis of variance. If no interaction effect was observed, results were next analyzed through correlated t-test (α = 0.05). Significant sex by time interactions were observed for arm total and lean mass, as well as a significant main effect of time showing a decrease in arm lean mass after the S&C session. Values before and after the S&C session that resulted in significant differences via correlated t-test are displayed in Table 1. Results revealed a significant decrease in total mass, arm and leg percent fat, and trunk lean mass, and an increase in leg lean mass.

Predicting V[Combining Dot Above]O2max From Treadmill Performance in American-Style Football Athletes.

Crouse, SF, Tolson, H, Lytle, J, Johnson, KA, Martin, SE, Green, JS, Oliver, J, Carbuhn, A, Lambert, B, and Bramhall, JP. Predicting V[Combining Dot Above]O2max from treadmill performance in American-style football athletes. J Strength Cond Res 33(4): 1028-1034, 2019-Prediction equations are often used to estimate V[Combining Dot Above]O2max in the general population but are lacking for American-style football (ASF) athletes. We sought to develop a regression model to estimate V[Combining Dot Above]O2max from treadmill exercise time in ASF athletes and compare our football V[Combining Dot Above]O2max model with 2 published prediction equations (Foster et al., 1984, and Bruce, 1973). American-style football athletes (N = 472, age = 18 ± 1 year, height = 186.1 ± 8.2 cm, and body mass = 101.8 ± 20.4 kg) underwent treadmill exercise to voluntary exhaustion (Bruce protocol). Maximal exercise time was recorded in minutes (Tmin), and V[Combining Dot Above]O2max was simultaneously measured (M-V[Combining Dot Above]O2max, mlO2·kg·min) by an automated gas-analysis system. Athletes were then randomly divided into validation and cross-validation groups (n = 236). Linear regression yielded estimates of V[Combining Dot Above]O2max from Tmin as follows: validation V[Combining Dot Above]O2max = 4.012 × Tmin - 4.628 (r = 0.678, p < 0.001, and SEE = 4.07); cross-validation V[Combining Dot Above]O2max = 4.025 × Tmin - 4.693 (r = 0.661, p < 0.001, and SEE = -4.16). These equations had a cross-validation coefficient of 0.813 and a double cross-validation coefficient of 0.823. Differences between the slopes of the 2 equations were not significant (t-test, p = 0.9603). Because validation and cross-validation groups were not statistically different on any variables measured (multivariate analysis of variance, p > 0.05), all athletes were combined to yield our final prediction equation: football V[Combining Dot Above]O2max = 4.017 × Tmin - 4.644 (r = 0.670, p < 0.001, and SEE = 4.11). Repeated-measures analysis of variance demonstrated significant differences (p < 0.001) in estimates of V[Combining Dot Above]O2max among Foster (44.1 ± 6.1), Bruce (47.1 ± 5.5), and our football (45.1 ± 5.8) equations. Foster and Bruce V[Combining Dot Above]O2max estimates were also significantly different from M-V[Combining Dot Above]O2max ((Equation is included in full-text article.)diff = -0.975 and 1.995, respectively, p < 0.001). V[Combining Dot Above]O2max of ASF athletes can be reasonably estimated by our football prediction equation using maximal treadmill time as the predictor.

DEXA or BMI: clinical considerations for evaluating obesity in collegiate division I-A American football athletes.

OBJECTIVE: To evaluate the relationship between body mass index (BMI) and %body fat (%Fat) in collegiate football athletes (FBA) compared with age-matched/gender-matched general population volunteers (comparison group, CG) and compare body composition and overweight/obese frequencies by BMI between FBA and CG. DESIGN: Cross-sectional. SETTING: Two Division I-A (D-IA) universities in Texas. Integrative Health Technologies (San Antonio, Texas) laboratory. PARTICIPANTS: Football athletes (n = 156, 20.0 ± 1.3 years, 185.6 ± 6.5cm, 103.3 ± 20.4 kg). Comparison group (n = 260, 21.5 ± 2.7 years, 179.0 ± 7.6 cm, 86.3 ± 20.9 kg). STATISTICAL ANALYSIS: Body mass index and bone densitrometry (DEXA) body composition were assessed. Regression was used to predict %Fat from BMI in CG and FBA. To compare %Fat, fat mass (FM), fat-free mass (FFM), and weight (WT) between CG, FBA, linemen, and non-linemen, 1 × 4 analysis of variance was used. Chi-square analysis was used to compare the frequency of BMI ≥25 between groups. RESULTS: Body mass index differently predicted %Fat for CG (r = 0.643, SE = 6.258) and FBA (r =0.769, SE = 4.416). Body mass index cutoffs for overweight/obese corresponded to the following %Fat in each group [BMI ≥25 = 19.9% (CG) and 11.1% (FBA); BMI ≥30 = 27.3% (CG) and 20.2% (FBA)]. Football athletes had significantly higher WT, BMI, FFM, and frequency of BMI ≥25 with lower %Fat and FM than CG (α < 0.05). Linemen had the highest WT, BMI, FFM, %Fat, and frequency of BMI ≥25. CONCLUSIONS: The relationship between BMI and %Fat differed between CG and FBA. Using current BMI thresholds for obesity in FBA may result in misleading inferences about health risk.

Resistance training dose response in combined endurance-resistance training in patients with cardiovascular disease: a randomized trial.

OBJECTIVE: To compare the effectiveness of 2 different volumes of resistance training (RT) combined with aerobic training in residential cardiac rehabilitation (CR). DESIGN: Randomized prospective cohort study. SETTING: Center for inpatient CR. PARTICIPANTS: Patients (N=295) with a mean age ± SD of 62.7±11.7 years participated in the study. INTERVENTIONS: Patients were randomly divided into 2 groups (group 1 and group 2) with different volumes of RT; 2 sets × 12 repetitions (REPS) (group 1) and 3 sets × 15 REPS (group 2) per session, 2 times per week; each RT session consisting of 10 different resistance exercises. In addition, patients also completed continuous moderate intensity aerobic training composed of cycle ergometry 6 times per week for 17±4 minutes (mean ± SD) and walking 5 times per week for 45 minutes. MAIN OUTCOME MEASURES: At entry and after 26±4 (mean ± SD) days of CR, blood pressure, heart rate, maximal oxygen consumption, and maximal power determined during cycle ergometry, strength determined via RT, and blood biochemistries were assessed. Data were analyzed via a 2-way (group × time) repeated measures analysis of variance. RESULTS: Statistical analysis revealed equivalent improvements in exercise capacity, muscular strength, hemodynamics, and blood chemistries regardless of RT volume (comparison-wise type I error rate, α<.01). CONCLUSIONS: Our results show that nearly doubling (3 sets × 15 REPS vs 2 sets × 12 REPS) the volume of RT as part of a residential CR program does not yield further improvement in strength and cardiovascular risk factors.

Sport and training influence bone and body composition in women collegiate athletes.

This is a novel descriptive study to characterize off-season, preseason, and postseason bone and body composition measures in women collegiate athletes. From 2006 through 2008, 67 women collegiate athletes from 5 sports, softball (n = 17), basketball (n = 10), volleyball (n = 7), swimming (n = 16), and track jumpers and sprinters (n = 17) were scanned using dual energy X-ray absorptiometry (DXA) at 3 seasonal periods: (a) off-season = before preseason training, (b) preseason = after preseason training, and (c) postseason = after competitive season. Dual energy X-ray absorptiometry scans were analyzed for total body mass, lean mass (LM), fat mass (FM), percent body fat (%BF), bone mineral content, bone mineral density (BMD), arm BMD, leg BMD, pelvis BMD, and spine BMD. Data were analyzed between sports using analysis of variance (ANOVA) with Tukey post hoc follow-ups, and within each sport using repeated-measures ANOVA and LSD; alpha < 0.05. Significant off-season to preseason or postseason changes in %BF, LM, and BMD within each sport were as follows, respectively: softball, -7, +4, +1%; basketball, -11, +4, +1%; volleyball, unchanged, unchanged, +2%; swimming, unchanged, +2.5%, unchanged; track jumpers and sprinters, -7, +3.5, +1%. Comparisons among athletes in each sport showed bone measurements of swimmers averaged 4-19% lower than that of athletes in any other sport, whereas for track jumpers and sprinters, %BF and FM averaged 36 and 43% lower compared with other sports at all seasonal periods. Values for athletes playing basketball and volleyball were most similar, whereas softball athletes' values fell between all other athletes. These data serve as sport-specific reference values for comparisons at in-season and off-season training periods among women collegiate athletes in various sports.

Short-term residential cardiac rehabilitation reduces B-type natriuretic peptide.

BACKGROUND: The inactive N-terminal pro-BNP (NT-proBNP) serves as a marker of heart failure. We evaluated the effects of moderate exercise on NT-proBNP and other cardiovascular disease risk factors in 359 consecutive patients admitted for residential cardiovascular rehabilitation. METHODS AND RESULTS: Patients underwent cycle ergometry, blood sampling, and fasting glucose tests at the beginning and end of 25+/-4 days of the exercise program. Maximal oxygen uptake (VO2max) was estimated from the maximal watts achieved. The program consisted of cycling for 17+/-4 min, 6 times/week, and daily walking for 45 min at intensity of 60-70% of the individual maximal heart rate (HR). Patients underwent echocardiographic examination and were categorized according to left ventricular ejection fraction. NT-proBNP decreased to 29% (P = 0.001) for entire group after training. Maximal performance and VO2max improved significantly (P = 0.001). NT-proBNP was inversely related to pulse pressure at maximal exercise (-0.39), HR range (-0.35), and HR recovery in 1 min (-0.28). CONCLUSION: Four weeks of exercise reduced NT-proBNP, independent of left ventricular ejection fraction, and improved physical fitness and blood lipid profiles. NT-proBNP as a prognostic biomarker of heart failure patients was reduced and was inversely related to maximal performance and VO2max.

Electrocardiograms of collegiate football athletes.

BACKGROUND: The prevalence of electrocardiogram (ECG) abnormalities in American collegiate football athletes is virtually unknown. PURPOSE: The purpose of this study was to characterize the type and frequency of ECG abnormalities in a sample of football athletes entering National Collegiate Athletic Association (NCAA) Division I Football Bowl Subdivision university program. METHODS: Over a 4-y period, resting and exercise 12-lead ECG recordings were analyzed by a cardiologist from 68 freshmen and 9 transfer football athletes (n=77; 54 African-Americans and 23 Caucasians, aged 18 +/- 1 y, height=1.89 +/- 0.06 m, weight= 104.4 +/- 19.8 kg) as part of their entry physical examination. RESULTS: A total of 79% of the athletes demonstrated at least 1 abnormal ECG finnding, and significantly more African-America athletes (85%) than Caucasian (65%) athletes. Wolff-Parkinson-White (WPW) syndrome was found in 1 African-American player. Frequencies of various ECG abnormal findings in all athletes were: left ventricular hypertrophy = 64.5%, ST-T wave = 6.5%, interventricular conduction delay = 2.6%, sinus bradycardia = 9.1%, sinus arrhythmia = 15.6%, first-degree atrioventricular (AV) block = 11.7%, left atrial enlargement = 48.1%, early repolarization = 33.8%, and right axis deviation = 20.8%. Average values for the PR (0.17 +/- 0.03 s), QRS (0.08 +/- 0.02 s), and QT intervals (0.38 +/- 0.05 s), P-wave duration (0.10 +/- 0.02 s), and QRS axis (79.1 +/- 18.2 degrees) were normal. The ECG responses to maximal treadmill exercise stress tests were evaluated as normal without ischemia or arrhythmias. CONCLUSION: Abnormal resting ECG findings are common in a sample of collegiate football athletes, exceeding the rate expected for their age, and are more frequent in African-American athletes as compared with Caucasian athletes.

Predicting Energy Expenditure of an Acute Resistance Exercise Bout in Men and Women.

The energy expenditure of resistance exercise (RE) is an important consideration for exercise prescription and weight management, yet prediction models are lacking. PURPOSE: This study aimed to develop regression equations to predict energy expenditure (kcal) for RE involving each major muscle group using commonly measured demographic and exercise variables as predictors. METHODS: Fifty-two healthy, active subjects (27 men, 25 women, age 20-58 yr, height 174.1 ± 10.5 cm, weight 188.7 ± 42.6 kg, V˙O2max 36.8 ± 9.2 mL·kg⋅min) were strength tested to estimate their one-repetition maximum 1 wk before their experimental RE bout. The experimental RE bout consisted of a warm-up set followed by 2-3 sets (2-min turnover) of 8-12 reps at 60%-70% of predicted one-repetition maximum for leg press, chest press, leg curl, lat pull, leg extension, triceps push down, and biceps curl. Kilocalories were estimated from V˙O2 measured continuously throughout the RE bout via an automated metabolic cart. Total exercise volume (TV) was calculated as sets × reps × weight lifted. Multiple linear regression (stepwise removal) was used to determine the best model (highest adjusted R) to predict the kilocalorie consumption of the total workout and of the individual RE lifts. RESULTS: The derived regression equation for the net kilocalorie consumption of an RE bout was as follows: total net kilocalorie = 0.874 (height, cm) - 0.596 (age, yr) - 1.016 (fat mass, kg) + 1.638 (lean mass, kg) + 2.461 (TV × 10) - 110.742 (R = 0.773, SEE = 28.5 kcal). Significant equations were also derived for individual lifts (R = 0.62 to 0.83). CONCLUSIONS: Net energy expenditure for a total RE bout and for individual RE can be reasonably estimated in adult men and women using commonly measured demographic and RE variables.

Morphological profiles for first-year National Collegiate Athletic Association Division I football players.

We are aware of no published research in which the morphological profiles of first-year collegiate football players are characterized. In light of the known association between obesity and cardiovascular disease and recent data suggesting an increased frequency of obesity and early death in professional football players, we have compiled a morphological profile of 65 freshman and transfer recruits (age = 18.4 +/- 1.2 years) from a National Collegiate Athletic Association (NCAA) Division I football program. Measured variables included height (HT), body mass (BM), and body fat percentage (BF) (hydrostatic method). Body mass index (BMI) was calculated using HT and weight variables. Individuals were grouped by player position for descriptive statistical analysis. The means for all 65 players were as follows: HT = 189 +/- 7 cm, BM = 106.5 +/- 4.8 kg, BF = 15 +/- 7%, and BMI = 29.8 +/- 4.7. Mean data from these collegiate athletes were compared to recently published data from professional players. By comparison, the average HT, BM, BF, and BMI of the professional football athletes were 188 +/- 4 cm, 107 +/- 4.8 kg, 14 +/- 5%, and 30.1 +/- 1.9, respectively. While the average BMIs of the collegiate athletes in this study would be classified as overweight or obese, the BFs were found to be within an acceptable range for health status. These data provide important indicators of morphological characteristics and BM health risks of new football recruits at a Division I university. The data presented also provide an historical basis for (a) evaluating both the conditioning of first-year incoming athletes, (b) determining the physical development of the athletes as they progress through the training program, and (c) charting the morphological changes that occur in collegiate football throughout time that may contribute to increased health risks to the athletes.

Performance and blood pressure characteristics of first-year national collegiate athletic association division I football players.

The authors were aware of no published studies in which the performance characteristics of first-year National Collegiate Athletic Association Division I collegiate football players were reported. From 2003 to 2006, 73 freshman and 12 transfer football recruits were tested before twice-a-day practices for bench press (BP), squat (SQ), power clean (PC), vertical jump (VJ), calculated jump power (CP), treadmill endurance capacity (Vo2peak), and maximal treadmill time (MTT). Individuals were grouped by player position for descriptive statistical analysis. As a group, offensive linemen (OL), defensive linemen (DL), linebackers (LB), tight ends (TE), and running backs (RB) averaged 152.8 kg for BP, 210.5 kg for SQ, 127.3 kg for PC, and 224.2 W for CP. These values were 22% to 30% higher than those for quarterbacks (QB), wide receivers (WR), defensive backs (DB), and kickers (K), who together averaged 120.2 kg for BP, 163.4 kg for SQ, 104.6 kg for PC, and 172.4 W for CP. Quarterbacks, WR, DB, and K as a group showed the highest MTT (13:13 m.s) and Vo2peak values (47.24 mL.kg.min), 15% to 20% higher than those for OL, DL, LB, RB, and TE, who averaged 11:27 m.s for MTT and 39.51 mL.kg.min for Vo2peak. Running backs, TE, LB, DB, and WR averaged 82.56 cm for VJ, which was 14% higher than that for DL, QB, K, and OL, who averaged 72.72 cm. On the basis of average resting blood pressure, 23.5% (20 players) were categorized as hypertensive (i.e., >/=140/90 mm Hg), 54% (46 players) as prehypertensive (i.e., 120-139/80-89 mm Hg), and 22.5% (19 players) as normal (i.e., <120/80 mm Hg). These data serve as a basis for comparisons among other Division I programs, benchmarking development and improvement through training, and creating position performance norms for incoming football athletes.

Comparison of cardiorespiratory responses of moderately trained men and women using two different treadmill protocols.

In practice, the Bruce protocol is the most commonly used treadmill protocol to assess maximal oxygen consumption (V(.-)O2max). It has been suggested that a running protocol (e.g., Astrand) may elicit a comparatively higher V(.-)O2max and different cardiorespiratory responses when applied to moderately trained runners. Thus, the purpose of this study was to compare V(.-)O2max and other cardiorespiratory responses as elicited by the standard Bruce and a modified Astrand treadmill protocol in moderately trained runners. Fifteen women (age = 21 years, height = 171.5 cm, weight = 63 kg, and body fat = 18%) and 15 men (age = 26 years, height = 177 cm, weight = 72 kg, and body fat = 9%) who were moderately trained runners completed a standard Bruce and modified Astrand protocol (random order), separated by approximately 7 days. Heart rate, Borg ratings of perceived exertion, blood pressure, and pulmonary gas exchange variables were measured during the exercise tests using standard laboratory procedures. This study revealed V(.-)O2max values between the Bruce protocol (51.3 +/- 11.6 ml x kg(-1) x min(-1)) and modified Astrand (51.5 +/- 10.9 ml x kg(-1) x min(-1)) were not significantly different in either the men or the women. However, the Bruce protocol elicited significantly higher maximum treadmill time in men and maximum respiratory exchange ratio (RERmax) and maximum minute ventilation (VEmax) values in both genders. Conversely, the modified Astrand elicited a higher HRmax. These data suggest that V(.-)O2max in both moderately trained men and women runners is independent of treadmill protocol despite differences in HRmax, RERmax, and VEmax.

Exercise raises high-density lipoprotein cholesterol in men after consumption of ground beef with a high but not low monounsaturated fatty acid-saturated fatty acid ratio.

Exercise and diets with higher monounsaturated fatty acid (MUFA):saturated fatty acid (SFA) ratios are independently linked to improved blood lipid profiles, yet interactive effects in men have not been studied. We hypothesized that dietary ground beef with a high MUFA:SFA ratio (HR = 1.1) would augment the beneficial changes in the lipid profile induced by exercise compared to dietary ground beef with a lower MUFA:SFA ratio (LR = 0.71). Untrained men (n = 13, age = 35 ± 12 y, weight = 91.4 ± 14.2 kg, body mass index = 27.8 ± 3.3kg/m(2)) consumed 5 HR or LR 114 g ground beef patties weekly for 5 weeks (random order) interspersed with a 4-week self-selected (SS) washout diet. One session of exercise (70% VO2max, 1675 kJ) was completed at the end of HR and LR diets, and again after a 5-week SS diet. Diets and physical activity were otherwise not controlled. Fasting blood samples for lipid and lipoprotein analyses were obtained 30 min before and 24 h after exercise. Subjects reported no other changes in diets or physical activity patterns, and body weight and body mass index did not change over the study duration. Diet (3) × Exercise Time (2) repeated measures analysis of variance (α = .05) and follow-up analyses revealed that blood concentrations (mmol/L ± SD) of total cholesterol (5.07 ± 1.16 to 5.73 ± 1.36), high-density lipoprotein cholesterol (HDL-C) (1.19 ± 0.20 to 1.36 ± 0.29), HDL2-C (0.24 ± 0.08 to 0.28 ± 0.11), HDL3-C (0.94 ± 0.14 to 1.08 ± 0.20), and non-HDL-C (3.88 ± 1.24 to 4.37 ± 1.38) were significantly elevated with exercise after the HR beef diet, but not after LR and SS diets. Thus, in healthy, untrained men the dietary beef MUFA:SFA ratio affects the blood lipid response to a single session of aerobic exercise.

The effects of exercise training on abdominal visceral fat, body composition, and indicators of the metabolic syndrome in postmenopausal women with and without estrogen replacement therapy: the HERITAGE family study.

The purpose of this research was to investigate the effects of apriori estrogen replacement therapy (ERT) and endurance exercise training in postmenopausal women on abdominal visceral fat (AFV) and other selected variables related to body composition and the metabolic syndrome (MS). Forty-eight healthy and previously sedentary postmenopausal women (mean age, 54.3 years) who were enrolled in the HERITAGE Family Study (HFS) served as subjects. Of these 48 women, 18 were currently taking ERT and the remaining 30 were taking no supplemental estrogen (NHRT). Computed tomography (CT) scans were used to assess AVF as well as total abdominal fat (TAF) and abdominal subcutaneous fat (ASF). Body mass index (BMI) and waist-to-hip ratios (WHR) were calculated while body fat percentage (%FAT) and total fat mass (FATM) was assessed using underwater weighing. Blood assays for HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), and triglycerides (TG) were conducted at a Centers for Disease Control (CDC) certified laboratory, while blood pressure measurements were assessed using an automated system. All measurements were obtained in duplicate before and after a regimen of endurance exercise training. Analysis of variance (ANOVA) showed AVF to be an average of 31.6 cm(2) less in the women receiving ERT, but lost statistical significance when AVF was adjusted for FATM. Mean values for TAF, ASF, and waist girth were also less in the women receiving ERT, but only waist girth achieved statistical significance. No differences were found in BMI or %FAT, but mean WHR was 5% smaller in the ERT group. Baseline values for HDL-C was higher and LDL-C lower in the ERT group. Prevalence of the MS tended to be greater in the NHRT group, but did not achieve statistical significance. There were no differences in training responses in any of the body composition variables between groups, however, in the ERT group LDL-C decreased with training while TG increased. It was concluded that postmenopausal women taking ERT tended to have lower values of AVF and other indicators of body composition, a more favorable lipid profile, and a slightly reduced risk of the MS when compared with women not taking supplemental hormones. Also exercise training did not improve the overall MS status of either group, as LDL-C status improved in the ERT group while TG decreased in the NHRT group.

Effects of resistance, endurance, and concurrent exercise on training outcomes in men.

UNLABELLED: The specificity of training principle predicts that combining resistance and endurance training (concurrent training) could interfere with the maximum development of strength and endurance capacity that results from either type of training alone. PURPOSE: To determine whether endurance and resistance training performed concurrently produces different performance and physiologic responses compared with each type of training alone. METHODS: Untrained male volunteers were randomly assigned to one of three groups: endurance training (ET, N = 12); resistance training (RT, N = 13); and concurrent training (CT, N = 16). The following measurements were made on all subjects before and after 12 wk of training: weight, percent body fat, peak oxygen consumption (VO(2peak)), isokinetic peak torque and average power produced during single-leg flexion and extension at 60 and 180 degrees.s, one-repetition maximum (1RM) leg press, 1RM bench press, vertical jump height, and calculated jump power. RESULTS: Weight and lean body mass (LBM) increased significantly in the RT and CT groups (P < 0.05). Percent body fat was significantly decreased in the ET and CT groups. VO(2peak) was significantly improved only in the ET group. Peak torque during flexion and extension at 180 degrees.s(-1) increased in the RT group. Improvements in 1RM leg press and bench press were significant in all groups, but were significantly greater in the RT and CT compared to the ET group. Jump power improved significantly only in the RT group, and no group showed a significant change in vertical jump height. CONCLUSIONS: Concurrent training performed by young, healthy men does not interfere with strength development, but may hinder development of maximal aerobic capacity.

Menopause, estrogen, and training effects on exercise hemodynamics: the HERITAGE study.

PURPOSE: To investigate the influences of menopause, hormone replacement, and endurance exercise training on cardiovascular hemodynamics and oxygen uptake parameters during exercise in women. METHODS: Subjects were 338 premenopausal women, 29 postmenopausal women taking hormone replacement, and 28 postmenopausal women not taking hormone replacement, all enrolled in the HERITAGE Family Study. Hemodynamic and oxygen uptake data were gathered on a cycle ergometer at 50 watts (W), 60% peak oxygen uptake, and at peak exercise, both before and after a 20-wk regimen of endurance exercise training on a cycle ergometer. RESULTS: Systolic blood pressure (SBP) during peak exercise was found to be an average of 14 mm Hg less in postmenopausal women receiving hormones than in those not receiving hormones. Furthermore, menopause was associated with a 26.2 mm Hg higher SBP at 50 W power output, which remained physiologically significant after adjustment for age. At 50 W, postmenopausal women not taking hormones showed a 13.8 mm Hg greater training-induced reduction in SBP than those taking hormones. CONCLUSION: It was concluded that hormone replacement may be associated with a vasodilatory reserve at high exercise intensities and that endurance exercise training elicits favorable hemodynamic and oxygen uptake adaptations during exercise that are, in most instances, independent of menstrual status or hormone replacement.

Heart disease risk perception in college men and women.

The authors sought to assess the perception of risks for coronary heart disease (CHD) in college men and women. They surveyed 470 undergraduates from 2 major 4-year institutions who completed a questionnaire that measured perceived risks for heart disease. Sixty-eight percent of the respondents rated their risks as lower or much lower than those of their peers, indicating a clear optimistic bias. The research also revealed that the students who exercised regularly rated their risk of coronary disease lower than those who did not do so. In addition, women perceived a number of risk markers to be more potent or causative factors than men did. A significant number of participants did not comprehend commonly understood causal relationships associated with heart disease risk. The findings in this preliminary investigation suggest that college men and women do not accurately perceive their risks for developing heart disease.

Predicting football players' dual-energy x-ray absorptiometry body composition using standard anthropometric measures.

CONTEXT: The recent increase in athlete size, particularly in football athletes of all levels, coupled with the increased health risk associated with obesity warrants continued monitoring of body composition from a health perspective in this population. Equations developed to predict percentage of body fat (%Fat) have been shown to be population specific and might not be accurate for football athletes. OBJECTIVE: To develop multiple regression equations using standard anthropometric measurements to estimate dual-energy x-ray absorptiometry %Fat (DEXA%Fat) in collegiate football players. DESIGN: Controlled laboratory study. PATIENTS AND OTHER PARTICIPANTS: One hundred fifty-seven National Collegiate Athletic Association Division IA football athletes (age = 20 ± 1 years, height = 185.6 ± 6.5 cm, mass = 103.1 ± 20.4 kg, DEXA%Fat = 19.5 ± 9.1%) participated. MAIN OUTCOME MEASURE(S): Participants had the following measures: (1) body composition testing with dual-energy x-ray absorptiometry; (2) skinfold measurements in millimeters, including chest, triceps, subscapular, midaxillary, suprailiac, abdominal (SFAB), and thigh; and (3) standard circumference measurements in centimeters, including ankle, calf, thigh, hip (AHIP), waist, umbilical (AUMB), chest, wrist, forearm, arm, and neck. Regression analysis and fit statistics were used to determine the relationship between DEXA%Fat and each skinfold thickness, sum of all skinfold measures (SFSUM), and individual circumference measures. RESULTS: Statistical analysis resulted in the development of 3 equations to predict DEXA%Fat: model 1, (0.178 · AHIP) + (0.097 · AUMB) + (0.089 · SFSUM) - 19.641; model 2, (0.193 · AHIP) + (0.133 · AUMB) + (0.371 · SFAB) - 23.0523; and model 3, (0.132 · SFSUM) + 3.530. The R(2) values were 0.94 for model 1, 0.93 for model 2, and 0.91 for model 3 (for all, P < .001). CONCLUSIONS: The equations developed provide an accurate way to assess DEXA%Fat in collegiate football players using standard anthropometric measures so athletic trainers and coaches can monitor these athletes at increased health risk due to increased size.

Periodontal and coronary heart disease in patients undergoing coronary angiography.

Periodontal inflammation has been implicated in atherosclerosis and coronary heart disease (CHD). Coronary angiography (CA) is used in the assessment of CHD; only a few studies have evaluated periodontal disease (PD) and angiographic measures of coronary atherosclerosis. The aim of this study was to investigate the association between CHD and PD. In this prospective epidemiologic study, 466 patients underwent CA and were assessed for PD. All patients underwent physical, laboratory, cardiac, and dental examination including dental x-rays. Periodontal disease and coronary angiograms were evaluated blindly by a dentist and 2 cardiologists, respectively. A coronary stenosis greater than 50% was ruled as CHD. Periodontal disease was defined and measured with the Community Periodontal Index of Treatment Needs (CPITN); and if at least 2 sextants (segments dividing mandible and maxilla into 6) were recorded as having CPITN of at least 3 (signifying that sextant had periodontal pocket depth ≥ 3.5 mm), the patient was coded as having PD. Three-hundred forty-nine patients (74.9%) had CHD assessed by CA The CHD patients had PD in 55.6% vs 41.9% in the non-CHD patients (P < .01). The CPITN scores were significantly higher in patients with vs without CHD, 2.43 vs 2.16, respectively (P = .023). After adjusting for age, sex, and risk factors for atherosclerosis with additional inclusion of C-reactive protein and erythrocyte sedimentation rate, PD remained significantly related to CHD (odds ratio = 1.9; 95% confidence interval, 1.2-3.1). Other predictors for CHD were male sex, age, high-density lipoprotein cholesterol, and diabetes. Our results demonstrate an increased odds ratio for angiographically determined CHD in patients with PD and that CHD and PD may cluster in particular groups of a population. Our data indicate that PD represents a potentially modifiable risk factor that is both preventable and treatable with predictable treatments that pose negligible risk.

VO2 prediction and cardiorespiratory responses during underwater treadmill exercise.

We compared cardiorespiratory responses to exercise on an underwater treadmill (UTM) and land treadmill (LTM) and derived an equation to estimate oxygen consumption (VO2) during UTM exercise. Fifty-five men and women completed one LTM and five UTM exercise sessions on separate days. The UTM sessions consisted of chest-deep immersion, with 0, 25, 50, 75, and 100% water-jet resistance. All session treadmill velocities increased every 3 min from 53.6 to 187.8 m x min(-1). Cardiorespiratory responses were similar between LTM and UTM when jet resistance for UTM was 50%. Using multiple regression analysis, weight-relative VO2 could be estimated as: VO2 (mLO2 c kg(-1) x min(-1)) = 0.19248 x height (cm) + 0.17422 x jet resistance (% max) + 0.14092 x velocity (m x min(-1)) -0.12794 x weight (kg)-27.82849, R2 = .82. Our data indicate that similar LTM and UTM cardiorespiratory responses are achievable, and we provide a reasonable estimate of UTM VO2.

Comparative efficacy of water and land treadmill training for overweight or obese adults.

PURPOSE: No known previous research has been published to explore the efficacy of underwater treadmill (UTM) exercise training for the obese. Thus, the purpose of this study was to compare changes in physical fitness, body weight, and body composition in physically inactive, overweight, and obese adults after 12 wks of land treadmill (LTM) or UTM training. METHODS: Fifty-seven physically inactive, overweight, and obese men (n = 25) and women (n = 32) participated in this investigation. The mean +/- SEM age, weight, body mass index (BMI), and V O2max upon entry were 44 +/- 2 yr, 90.5 +/- 2.4 kg, 30.5 +/- 0.7 kg.m, and 27.1 +/- 0.7 mL O2.kg.min, respectively. Subjects were randomly assigned to exercise three times per week for 12 wk on either LTM (n = 29) or UTM (n = 28) matched for intensity and volume. Session volume was progressively increased from 250 to 500 kcal per session by week 6 and remained at 500 kcal through week 12. Before and after training, V O2max was assessed by the Bruce treadmill protocol with open-circuit calorimetry, and body composition was assessed by dual-energy ray absorptiometry. Data were analyzed by a 2 (training) x 2 (exercise mode) x 2 (gender) ANOVA repeated across training (alpha = 0.05). RESULTS: Training responses were not different between genders. After either UTM or LTM training, V O2max was significantly increased (+3.6 +/- 0.4 mL O2.kg.min), whereas body weight (-1.2 +/- 0.3 kg), BMI (-0.56 +/- 0.11 kg.m), body fat percentage (-1.3% +/- 1.3%), and fat mass (-1.1 +/- 0.3 kg) were significantly reduced (pooled means for UTM and LTM). Regional leg lean body mass (LBM) was significantly increased with both CTM and UTM (0.4 +/- 0.3 and 0.8 +/- 0.2 kg, respectively). An increase in total LBM approached significance with UTM training only (+0.6 +/- 0.3 kg, P = 0.0599). CONCLUSIONS: UTM and LTM training are equally capable of improving aerobic fitness and body composition in physically inactive overweight individuals, but UTM training may induce increases in LBM.