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The purpose of this study was to develop a regression equation to predict maximal oxygen uptake (VO2max) based on nonexercise (N-EX) data. All participants (N = 100), ages 18-65 years, successfully completed a maximal graded exercise test (GXT) to assess VO2max (M = 39.96 mL x kg(-1) x min(-1), SD = 9.54). The N-EX data collected just before the maximal GXT included the participant's age; gender; body mass index (BMI); perceived functional ability (PFA) to walk, jog, or run given distances; and current physical activity (PA-R) level. Multiple linear regression generated the following N-EX prediction equation (R = .93, SEE = 3.45 mL x kg(-1) x min(-1), % SEE = 8.62): VO2max (mL x kg(-1) x min(-1)) = 48.0730 + (6.1779 x gender; women = 0, men = 1) - (0. 2463 x age) - (0.6186 x BMI) + (0.7115 x PFA) + (0.6709 x PA-R). Cross validation using PRESS (predicted residual sum of squares) statistics revealed minimal shrinkage (R(p) = .91 and SEE(p) = 3.63 mL x kg(-1) x min(-1)); thus, this model should yield acceptable accuracy when applied to an independent sample of adults (ages 18-65 years) with a similar cardiorespiratory fitness level. Based on standardized beta-weights, the PFA variable (0.41) was the most effective at predicting VO2max followed by age (-0.34), gender (0.33), BMI (-0.27), and PA-R (0.16). This study provides a N-EX regression model that yields relatively accurate results and is a convenient way to predict VO2max in adult men and women.

Excess postexercise oxygen consumption (EPOC) may describe the impact of previous exercise on energy metabolism. Ten males completed Resistance Only, Run Only, Resistance-Run, and Run-Resistance experimental conditions. Resistance exercise consisted of 7 lifts. Running consisted of 25 minutes of treadmill exercise. Vo(2) was determined during treadmill exercise and after each exercise treatment. Our findings indicated that treadmill exercise Vo(2) was significantly higher for Resistance-Run compared with Run-Resistance and Resistance Only at all time intervals. At 10 minutes postexercise, Vo(2) was greater for Resistance Only and Run-Resistance than for Resistance-Run. At 20 and 30 minutes, Vo(2) following Resistance Only was significantly greater than following Run Only. In conclusion, EPOC is greatest following Run-Resistance; however, treadmill exercise is more physiologically difficult following resistance exercise. Furthermore, the sequence of resistance and treadmill exercise influences EPOC, primarily because of the effects of resistance exercise rather than the exercise combination. We recommend performing aerobic exercise before resistance exercise when combining them into 1 exercise session.

Malonyl-CoA, the inhibitor of carnitine acyltransferase I, is an important regulator of fatty acid oxidation and ketogenesis in the liver. Muscle carnitine acyltransferase I has previously been reported to be more sensitive to malonyl-CoA inhibition than is liver carnitine acyltransferase I. Fluctuations in malonyl-CoA concentration may therefore be important in regulating the rate of fatty acid oxidation in muscle during exercise. Male rats were anesthetized (pentobarbital via venous catheters) at rest or after 30 min of treadmill exercise (21 m/min, 15% grade). The gastrocnemius/plantaris muscles were frozen at liquid N2 temperature. Muscle malonyl-CoA decreased from 1.66 +/- 0.17 to 0.60 +/- 0.05 nmol/g during the exercise. This change was accompanied by a 31% increase in cAMP in the muscle. The decline in malonyl-CoA occurred before muscle glycogen depletion and before onset of hypoglycemia. Plasma catecholamines, corticosterone, and free fatty acids were all significantly increased during the exercise. This exercise-induced decrease in malonyl-CoA may be important for allowing the increase in muscle fatty acid oxidation during exercise.

To assess test-retest reliability scores on 16 balance tests of 21 individuals with Down syndrome whose ages ranged from 5 to 31 yr., participants performed a standing test on firm and soft surfaces with the eyes open and closed, the balance subset of the Bruininks-Oseretsky test, full turn, timed-up-and-go test, forward reach, and sit-to-stand. Each participant completed all 16 tests twice in one day and then again on a subsequent day for a total of 4 sessions. The interclass reliability correlation coefficients (ICC) value for each measure of balance varied considerably by age and sex. Based on having an ICC > .50, only 3 tests were reliable in young males and young females, whereas 5 tests could reliably be used in adult females and 9 tests could reliably be used in adult males. The results of this study raise suspicions as to the reliability of tests commonly used to assess balance and differences in reliability due to age and sex. Results of balance tests should be interpreted with caution in males and females with Down syndrome across the age span.

BackgroundThe Functional Movement Screen (FMS™) has become increasingly popular for identifying functional limitations in basic functional movements. This exploratory and descriptive study was undertaken to confirm feasibility of performing the FMS™ in older active adults, assess prevalence of asymmetries and to evaluate the relationship between functional movement ability, age, physical activity levels and body mass index (BMI).MethodsThis is an observational study; 97 men (n = 53) and women (n = 44) between the ages of 52 and 83 participated. BMI was computed and self-reported physical activity levels were obtained. Subjects were grouped by age (5-year intervals), BMI (normal, over-weight, and obese) and sex. Each participant's performance on the FMS™ was digitally recorded for later analysis.ResultsThe youngest age group (50–54 years) scored highest in all seven tests and the oldest age group (75+) scored lowest in most of the tests compared to all other age groups. The subjects in the “normal weight” group performed no different than those who were in the “overweight” group; both groups performed better than the “obese” group. Of the 97 participants 54 had at least one asymmetry. The pairwise correlations between the total FMS™ score and age (r = −0.531), BMI (r = −0.270), and the measure of activity level (r = 0.287) were significant (p < 0.01 for all).ConclusionFMS™ scores decline with increased BMI, increased age, and decreased activity level. The screen identifies range of motion- and strength-related asymmetries. The FMS™ can be used to assess functional limitations and asymmetries. Future research should evaluate if a higher total FMS™ score is related to fewer falls or injuries in the older population.

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This study sought to develop a regression model to predict maximal oxygen uptake (VO 2max ) based on submaximal treadmill exercise (EX) and non-exercise (N-EX) data involving 116 participants, ages 18-65 years. The EX data included the participants' self-selected treadmill speed (at a level grade) when exercise heart rate first reached at least 70% of predicted maximum heart rate (HR max ; 220 -age) by the end of any one of three 4-min consecutive stages involving walking (3.0-4.0 mph; Stage 1), jogging (4.1-6.0 mph; Stage 2), and running (> 6.0 mph; Stage 3). The N-EX data included various demographic (age, gender), biometric (body mass), and questionnaire (participants' perceived functional ability [PFA] to walk, jog, or run given distances, and their self-reported level of physical activity [PA-R]) information. All participants (n = 100) who completed the study requirements and successfully achieved a maximal level of exertion during a graded exercise test (GXT) to assess VO 2max (mean ± SD; 41.39 ± 9.15 ml · kg -1 · min -1 ) were included in the data analysis. Stepwise regression was used to generate the following prediction equation (R = .94, SEE = 3.09 ml · kg -1 · min -1 ): VO 2max (ml · kg -1 · min -1 ) = 30.04 + (6.37 × gender; females = 0, males = 1) -(0.243 × age) -(0.122 × body mass) + (3.263 × ending self-selected treadmill speed; mph) + (0.391 × PFA) + (0.669 × PA-R). Each of the predictor variables were statistically significant (p < .001) and cross-validation procedures using PRESS (predicted residual sum of squares) statistics revealed minimal shrinkage (R p = .92 and SEE p = 3.29 ml · kg -1 · min -1 ). In summary, this submaximal treadmill test and accompanying regression model yields relatively accurate VO 2max estimates in healthy men and women (ages 18-65 years) using both EX and N-EX data.