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Biomedical subjects

B J Warren

Publications and source records attributed to B J Warren.

34 records · Page 2Linked to original sources
PubMed1993

Physical activity and serum lipids and lipoproteins in elderly women.

OBJECTIVE: The relationship between cardiorespiratory exercise and serum lipid and lipoprotein levels was studied in elderly women. DESIGN: Randomized controlled experimental design with a follow up of 12 weeks; cross-sectional comparison at baseline. SETTING: Community-living elders in university exercise facilities. PARTICIPANTS: Thirty-two apparently healthy, sedentary elderly Caucasian women, 67 to 85 years of age. Ten highly conditioned elderly women, 65 to 84 years of age, who were active in endurance competitions and had been training for 11.2 +/- 1.2 years, were recruited at baseline for cross-sectional comparisons. INTERVENTIONS: Sedentary subjects were randomized to either a walking or calisthenic group. Intervention groups exercised 30 to 40 minutes, 5 days a week for 12 weeks, with the walking group training at 60% heart rate reserve and the calisthenic group engaging in mild range-of-motion and flexibility movements that kept their heart rates close to resting levels. MEASUREMENTS: Serum lipids and lipoproteins, maximal aerobic capacity (VO2 max), four skinfolds, and dietary intake at baseline and after 5 and 12 weeks. RESULTS: When the highly conditioned group and combined group of sedentary subjects were compared at baseline, serum high-density lipoprotein cholesterol (HDL-C; 1.61 +/- 0.14 vs 1.27 +/- 0.05 mmol/L, respectively; P = 0.048) and triglycerides (1.29 +/- 0.15 vs 2.00 +/- 0.15, respectively; P = 0.002), but not total serum cholesterol (5.72 +/- 0.36 vs 5.72 +/- 0.19 mmol/L, respectively) and low-density lipoprotein cholesterol (LDL-C; 3.62 +/- 0.36 vs 3.72 +/- 0.18 mmol/L, respectively), were significantly different. Twelve weeks of moderate cardiorespiratory exercise improved the VO2max of the sedentary subjects 12.6% but did not result in any change in body weight, energy intake, dietary quality, or any of the serum lipids or lipoproteins. CONCLUSION: Highly conditioned and lean elderly women, when compared with their sedentary counterparts, had higher HDL-C and lower triglycerides, but similar total serum cholesterol and LDL-C values. However, twelve weeks of moderate cardiorespiratory exercise were not associated with an improvement in serum lipid or lipoprotein profiles in previously sedentary elderly women.

Aged↗
PubMed1993

Endocrine and performance responses to high volume training and amino acid supplementation in elite junior weightlifters.

To examine the effects of 1 week of high volume weightlifting and amino acid supplementation, 28 elite junior male weightlifters received either amino acid (protein) or lactose (placebo) capsules using double-blind procedures. Weightlifting test sessions were performed before and after 7 days of high volume training sessions. Serum concentrations of testosterone (Tes), cortisol (Cort), and growth hormone (GH) as well as whole blood lactate (HLa) were determined from blood draws. Lifting performance was not altered for either group after training, although vertical jump performance was not altered for either group after training, although vertical jump performance decreased for both groups. Both tests elicited significantly elevated exercise-induced hormonal and HLa concentrations. Significant decreases in postexercise hormonal and HLa concentrations from Test 1 to Test 2 were observed for both groups. Tes concentrations at 7 a.m. and preexercise decreased for both groups from Test 1 to Test 2, while the placebo group exhibited a decreased 7 a.m. Tes/Cort. These data suggest that amino acid supplementation does not influence resting or exercise-induced hormonal responses to 1 week of high volume weight training, but endocrine responses did suggest an impending over-training syndrome.

Adolescent↗
PubMed1993

Physical activity and immune function in elderly women.

The relationship between cardiorespiratory exercise, immune function, and upper respiratory tract infection (URTI) was studied in elderly women utilizing a randomized controlled experimental design with a follow-up of 12 wk. Thirty-two sedentary, elderly Caucasian women, 67-85 yr of age, who met specific selection criteria, were randomized to either a walking or calisthenic group; 30 completed the study. Twelve highly conditioned elderly women, 65-84 yr of age, who were active in endurance competitions, were recruited at baseline for cross-sectional comparisons. Intervention groups exercised 30-40 min, 5 d.wk-1, for 12 wk, with the walking group training at 60% heart rate reserve and the calisthenic group engaging in mild range-of-motion and flexibility movements that kept their heart rates close to resting levels. At baseline, the highly conditioned subjects exhibited superior NK (119 +/- 13 vs 77 +/- 8 lytic units, P < 0.01) and T (33.3 +/- 4.9 vs 21.4 +/- 2.1 cpm x 10(-3) using PHA, P < 0.05) cell function, despite no differences in circulating levels of lymphocyte subpopulations. Twelve weeks of moderate cardiorespiratory exercise improved the VO2max of the sedentary subjects 12.6%, but did not result in any improvement in NK cell activity or T cell function. Incidence of URTI was lowest in the highly conditioned group and highest in the calisthenic control group during the 12-wk study, with the walkers in an intermediate position (chi-square = 6.36, P = 0.042). In conclusion, the highly conditioned elderly women in this study had superior NK and T cell function when compared with their sedentary counterparts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Effects of high- vs moderate-intensity exercise on natural killer cell activity.

The effect of 45 min of high- (80% VO2max) vs moderate- (50% VO2max) intensity treadmill exercise on natural killer cell cytotoxic activity (NKCA) was investigated in 10 well-conditioned (66.0 +/- 1.9 ml.kg-1.min-1), young males (22.1 +/- 1.3 yr). Blood samples were taken before and immediately after exercise, with three more samples taken during 3.5 h of recovery, and analyzed for proportion of NK cells (CD3-CD16+CD56+) and NKCA. Exercise at 80% vs 50% VO2max resulted in a greater immediate postexercise increase in proportion of NK cells, followed by a 1-h and 2-h decrease below preexercise levels for both intensity conditions. NKCA rose significantly above preexercise levels following high- but not moderate-intensity exercise. For both exercise intensity conditions, NKCA tended to drop below preexercise levels by 1 h postexercise, rising back to preexercise levels by 3.5 h postexercise. When NKCA was expressed on a per-NK cell basis, however, no change relative to preexercise levels occurred following moderate-intensity exercise, while a significant increase occurred after 2-h recovery from high-intensity exercise. These data demonstrate that both high- and moderate-intensity exercise are associated with significant shifts in circulating proportions of NK cells which significantly influence interpretation of NKCA data based on assays using separated mononuclear cells.

Adolescent↗
PubMed1992

Acute hormonal responses in elite junior weightlifters.

To date, no published studies have demonstrated resistance exercise-induced increases in serum testosterone in adolescent males. Furthermore, few data are available on the effects of training experience and lifting performance on acute hormonal responses to weightlifting in young males. Twenty-eight junior elite male Olympic-style weightlifters (17.3 +/- 1.4 yrs) volunteered for the study. An acute weightlifting exercise protocol using moderate to high intensity loads and low volume, characteristic of many weightlifting training sessions, was examined. The exercise protocol was directed toward the training associated with the snatch lift weightlifting exercise. Blood samples were obtained from a superficial arm vein at 7 a.m. (for baseline measurements), and again at pre-exercise, 5 min post-, and 15 min post-exercise time points for determination of serum testosterone, cortisol, growth hormone, plasma beta-endorphin, and whole blood lactate. The exercise protocol elicited significant (p less than or equal to 0.05) increases in each of the hormones and whole blood lactate compared to pre-exercise measures. While not being significantly older, subsequent analysis revealed that subjects with greater than 2 years training experience exhibited significant exercise-induced increases in serum testosterone from pre-exercise to 5 min post-exercise (16.2 +/- 6.2 to 21.4 +/- 7.9 nmol.l-1), while those with less than or equal to 2 years training showed no significant serum testosterone differences. None of the other hormones or whole blood lactate appear to be influenced by training experience.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Performance measures, blood lactate and plasma ammonia as indicators of overwork in elite junior weightlifters.

The effects of short-term overwork on performance measures, blood lactate, and plasma ammonia concentrations were examined in 28 elite junior weightlifters who participated in a 2 wk high volume resistance training camp. Performance testing (maximum effort vertical jump test and snatch lift) and blood chemistry analyses (ammonia and lactate) were conducted before (T1) and after (T2) 7 d of high volume training (2-3 workouts/d). Blood samples were collected from an antecubital vein at rest, preexercise, 5 min postexercise, and 15 min postexercise at T1 and T2. Results indicated a significant decrease from T1 to T2 in the maximum effort vertical jump test while the snatch lift test yielded no difference across time. Blood lactate and ammonia concentrations were significantly lower at 5 min postexercise at T2 while resting ammonia concentrations were significantly elevated at T2 compared to corresponding measures at T1. These data suggest possible early symptoms of overwork at T2 (decrease in performance of the maximum effort vertical jump test and the elevated resting ammonia concentrations); however, lower 5 min postexercise concentrations of lactate and ammonia at T2 indicated a positive adaptation to the 1 wk high volume resistance training period.

Adolescent↗
PubMed1992

The mental health of African-American and Caucasian-American women who are homeless.

1. Nurses can use research findings to educate other health professionals about homeless subcultures with attention to specific cultural and socioeconomic needs, as well as to develop interventions for homeless women. 2. Minority women are more susceptible to homelessness as they experience increased poverty levels and are often single mothers. Of all minority women, African-American women are the most vulnerable to physical and psychological illness. 3. In this study, 75% of the subjects had scores on a psychological assessment test that indicated they needed additional psychological testing.

Adolescent↗
PubMed1992

Effect of musculoskeletal development on the prediction of body density in females.

The purpose of this study was to determine if musculoskeletal development had a significant effect on the prediction of body density in females. Subjects consisted of 156 females aged 17 to 44 years. Subjects were divided into three groups on the basis of musculoskeletal development as determined by the Heath-Carter Anthropometric Somatotype mesomorphy rating. Anthropometric measurements included eight skinfold measures (tricep, subscapula, chest, midaxillary, abdomen, suprailiac, thigh, and calf), body diameters of the humerus and femur, and circumferences at five locations (waist, forearm, upper arm, calf, and gluteal). Residual lung volume was determined by the closed circuit oxygen dilution method prior to the measurement of body density by hydrostatic weighing. A regression equation was developed to predict body density from the sum of seven skinfolds, sum of seven skinfolds squared, age, and mesomorphy rating. A similar regression equation was developed using the sum of three skinfolds, sum of three skinfolds squared, and the other variables. Results indicated that mesomorphy rating did not contribute significantly to the prediction of body density in females. It was concluded that musculoskeletal development did not have a significant effect on the prediction of body density in females.

Adolescent↗
PubMed1987

Profound acidosis caused by isoniazid ingestion.

Isoniazid (INH) is the cause of one of the most common serious drug overdoses and can cause severe metabolic acidosis. We report a case of INH overdose that is most notable because the patient survived without apparent sequelae after experiencing an extremely low pH level (6.49). This is the lowest reported pH level with patient survival. Toxicity and pharmacology of INH and various aspects of metabolic acidosis are discussed.

Acidosis, Lactic↗