Bryan L. Haddock

The effects of acute moderate exercise on leukocyte and lymphocyte subpopulations

The extent and duration of changes in circulating leukocyte and lymphocyte subpopulations, cortisol, and catecholamines were examined in 12 women who walked 45 min at 60% VO2max in a laboratory setting. A two-factor, 2 x 6 design with repeated measures on both factors was utilized. The first factor was condition (exercise and rest), and the second factor was time (six points of measurement over a 24-h period), with treatment order counterbalanced. The 45-min walk, in comparison with rest in a seated position, was associated with a significant but moderate leukocytosis and lymphocytosis immediately following the walk. The leukocytosis was still evident after 3 h of recovery and was primarily due to a neutrophilia. The change in lymphocyte count, relative to baseline levels and the control condition, lasted less than 1.5 h, with an increase in the natural killer (CD16 and/or CD56) and cytotoxic T cell component (CD3 and CD16 and/or CD56) (NKCT) representing approximately two-thirds of the lymphocytosis and T cells (CD5) the other third. A significant decrease in the CD4:CD8 ratio was seen, with cytotoxic/suppressor (CD8) cells increasing and helper/inducer (CD4) cells demonstrating little change in comparison with baseline. This seems to have been due to a subpopulation of CD8 (low density antigen) cells, probably natural killer cells. The 45-min walk had no effect on plasma cortisol and epinephrine levels relative to the rest condition but was associated with a moderate increase in norepinephrine.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiorespiratory fitness and cardiovascular disease risk factors in postmenopausal women.

PURPOSE The purpose of the present study was to determine if individuals with high levels of cardiorespiratory fitness have better levels of the cardiovascular disease (CVD) risk factors of total cholesterol (TC), HDL cholesterol (HDL), total cholesterol/HDL cholesterol ratio (TC/HDL), triglycerides (TG), and fibrinogen (FIB) when compared with those with low fitness, in 283 nonsmoking, postmenopausal women. Second, we examined the relation between fitness and CVD risk after controlling for use of hormones and other possible confounding factors. METHODS These analyses were done on a subset of nonsmoking, postmenopausal women in the Aerobics Center Longitudinal Study (ACLS). Records of postmenopausal women who completed a preventive medicine physical examination between 1987 and 1995 were examined. Cardiorespiratory fitness level was determined by total treadmill time to exhaustion on a graded exercise test; CVD risk factors were assessed via blood analysis. RESULTS On cross-sectional regression analysis, fitness was significantly associated (P < or = 0.005) with TC (r2 = 0.08), TC/HDL (r2 = 0.12), TG (r2 = 0.09), and FIB (r2 = 0.06), and an increase in HDL (r2 = 0.04). After controlling for hormone status, age, year of testing, and blood glucose, each outcome variable remained significantly associated with cardiorespiratory fitness (P < 0.05). TC/HDL and TG continued to be significantly related to cardiorespiratory fitness after adjusting for body mass index (BMI) as a control variable (P < 0.01). The lack of significance between TC, HDL, and FIB with cardiorespiratory fitness after adjusting for BMI is likely due to the biological relationship between cardiorespiratory fitness and BMI (r2 = 0.19). CONCLUSIONS We conclude that cardiorespiratory fitness is an important independent determinant of blood lipid and FIB levels in nonsmoking postmenopausal women, with or without HRT.

Isokinetic Strength of Collegiate Baseball Pitchers During a Season

Pitching is suggested to expose the arm to physical stress that may lead to a decrease in strength. The purpose of this study was to examine the isokinetic internal and external rotational shoulder strength of Division II pitchers preseason, midseason, and postseason. The 9 pitchers were 23 ± 0.67 years of age and weighed 91.2 ± 3.14 kg. Each subject was evaluated utilizing a Biodex Isokinetic Dynamometer. Isokinetic internal and external concentric strength was assessed at 90° of shoulder abduction and 90° of elbow flexion at 300 and 450°·s−1 at each time point. A repeated-measures analysis of variance statistical analysis was performed using SPSS software. All data are reported as mean ± SEM. Mean internal peak torques at 300 and 450°·s−1 preseason, midseason, and postseason were 50.66 ± 2.27, 49.70 ± 2.54, and 51.70 ± 2.94 N·m and 37.14 ± 2.54, 37.36 ± 2.74, and 38.26 ± 2.50 N·m, respectively. Mean external peak torques at 300 and 450°·s−1 preseason, mid-season, and postseason were 30.16 ± 1.69, 29.50 ± 2.22, and 29.79 ± 2.08 N·m and 17.68 ± 2.15, 16.89 ± 2.46, and 18.20 ± 2.35 N·m, respectively. There were no differences in isokinetic internal or external concentric shoulder rotational mean peak torque of Division II pitchers at any speed tested or time point examined.

HEALTH-RELATED VARIABLES AND FUNCTIONAL FITNESS AMONG OLDER ADULTS

This study assesses the functional fitness of a convenient sample of older adults (>70 years), to examine correlations between functional fitness and several other health-related variables and to compare with criterion performance data as established by Rikli and Jones (2001). One hundred and seven community-dwelling older adults with an average age of 78.36 ± 5.60 years performed the Senior Fitness Test (SFT) and responded to several health-related questionnaires. The SFT scores were similar to the scores in the low-active group data published by Rikli and Jones (1999b). There was a strong correlation between the 30-second arm curl and the 2-minute step-in-place (r = .54, p < .01). More than one-half of the participants performed in the normal range or above normal range, according to the criterion performance data. This demonstrates a high level of functional fitness.

Measurement of Energy Expenditure while Playing Exergames at a Selfselected Intensity

Exergames have been suggested as a possible alternative to traditional exercise in the general population. The purpose of this study was to examine the heart rate (HR) and energy expenditure (EE) of young adults playing several different exergames, while self-selecting the component of the game to play and the intensity. A total of 117 participants, 18-35 years of age, were evaluated on one of four active video games. Participants were free to choose any component of the given game to play and they played at a self-selected intensity. The average HR and EE during the individual games were compared to resting conditions and to the American College of Sports Medicine (ACSM) guidelines. The HR and EE increased above resting conditions during each game (p<0.05). When the results of all games were combined, the HR was 125.4 ± 20.0 bpm and the average EE was 6.7 ± 2.1 kcal/min. This HR represents an average percent of heart rate reserve of 44.6 ± 14.1, high enough to be considered moderate intensity exercise. If performed for 30 minutes a day, five days per week, the average EE would be 1,005 kcals, enough to meet the ACSM recommendations for weekly EE. Therefore, at least some exergames could be a component of an exercise program.

Energy expenditure comparison between walking and running in average fitness individuals.

Abstract Wilkin, LD, Cheryl, A, and Haddock, BL. Energy expenditure comparison between walking and running in average fitness individuals. J Strength Cond Res 26(4): 1039–1044, 2012—Increased energy expenditure (EE) is a key component in maintaining a healthy body mass. Walking and running are 2 common aerobic activities that increase EE above resting values. The purpose of this study was to compare the EE of individuals with average fitness during a walk and run for 1600 meters at 86 m·min−1 and 160 m·min−1, respectively. In addition, EE after the walk and run was compared. Fifteen females and 15 males (21.90 ± 2.52 y; 168.89 ± 11.20 cm; 71.01 ± 17.30 kg; 41.51 ± 6.31 ml−1·kg−1·min−1) volunteered to participate. Each participant completed a V[Combining Dot Above]O2max test. In addition, oxygen consumption was measured at rest for 10 minutes before exercise, during the walk and run, and after the walk and run for 30 minutes of recovery. EE during exercise was 372.54 ± 78.16 kilojoules for the walk and 471.03 ± 100.67 kilojoules for the run. Total EE including excess postexercise EE was 463.34 ± 80.38 kilojoules and 664.00 ± 149.66 kilojoules for the walk and run, respectively. Postexercise EE returned to resting values 10 minutes after the walk and 15 minutes after the run. Walking and running are both acceptable activities that increase EE above rest and can be performed without the expense of a health club membership and meet adequate kilojoule expenditure according to American College of Sports Medicine guidelines.

Functional Fitness of Older Adults

The purpose of this study is to compare differences in the functional fitness of a group of older adults to determine if they are aging successfully, to analyze the differences in functional fitness between females and males, and to determine differences in four categories by sex. Participants were placed into four categories based on senior fitness test (SFT) scores. More than 50% of the participants had scores that placed them in the average or above average categories. The most common variables affecting scores for females were age and medications, and for males the most common variable was depression. In conclusion, older adults with average and above average functional fitness appear to age successfully.