Search Results

You are looking at 1 - 10 of 275 items for :

  • "aerobic capacity" x
Clear All
Restricted access

Linda D. Zwiren

This paper deals with the measurement of aerobic and anaerobic power in children, and how these capacities are affected by growth and training. The type of tests available, the selection of ergometer, establishment of criteria for determining whether a maximal value has been attained, and the limitations of the various expressions of maximal values are discussed. Aerobic capacity, when expressed in liters per minute, has been observed to increase with growth; when expressed relative to body weight, aerobic capacity has been shown to remain the same or decrease with age. Anaerobic capacity increases with age no matter how the values are expressed. Limited evidence suggests that training during prepubescence does not increase aerobic capacity beyond that expected from growth. Several methodological limitations of longitudinal studies are examined.

Restricted access

Mollie G. DeLozier, Richard G. Israel, Kevin F. O’Brien, Robert A. Shaw and Walter J. Pories

This investigation quantified body composition and aerobic capacity and examined the interrelationships of these measures in 20 morbidly obese females (M age = 34.6 yrs) prior to gastric bypass surgery. Fifteen subjects were hydrostatically weighed at residual lung volume in order to determine body composition. Eighteen subjects performed a maximal modified progressive treadmill test to determine aerobic capacity. Results indicated that the 15 subjects who were weighed hydrostatically were heavier (M wt = 132.34 kg) and fatter (M % fat = 53.18) than any previously described individuals. Relative weight, which is used as a criterion to determine surgery eligibility, was not significantly (p > .05) correlated to percent body fat. Mean aerobic capacity (V̇O2 = 14.99 ml • kg-1 mir-1) was comparable to Class III cardiac patients and was limited by the individuals’ extreme body weight. Since relative weight was shown to be an insensitive measure of obesity, it is recommended that percent fat be measured and used as a means to determine eligibility for gastric bypass surgery. Further study of these individuals is warranted in order to determine what effects large weight loss following surgery will have on parameters of body composition and aerobic capacity. Understanding how large weight loss affects these parameters will aid in designing effective postsurgical exercise rehabilitative programs for future patients.

Restricted access

Mariana F.M. Oliveira, Fabrizio Caputo, Ricardo D. Lucas, Benedito S. Denadai and Camila C. Greco

Purpose:

To identify the speed corresponding to anaerobic threshold using the D-max method for both blood lactate and biomechanical stroke parameters determined in an incremental swimming test and to compare this information with the speed corresponding to the maximal lactate steady state (SMLSS).

Methods:

Five male long-distance swimmers and 8 triathletes (N = 13; age 23.8 ± 9.5 y, height 1.76 ± 0.1 m, weight 71.3 ± 9.8 kg) performed the following protocols: maximal 400-m test to determine maximal aerobic speed (S400); 7 × 200-m incremental test to determine the speed corresponding to the D-max point on the blood lactate (SLa), stroke-rate (SSR), stroke-length (SSL), and stroke-index (SSI) responses; and two to four 30-min submaximal tests to determine the SMLSS.

Results:

SLA (1.18 ± 0.08 m/s), SSI (1.18 ± 0.08 m/s), SSR (1.17 ± 0.1 m/s), and SSL (1.16 ± 0.09 m/s) were not significantly different from each other or from SMLSS (1.13 ± 0.08 m/s). There were high correlations between SLA, SSI, SSR, SSL, and SMLSS (r = .91, .89, .85, and .80, respectively). The typical errors of estimate for SLA (3.2%), SSI (3.7%), SSR (4.1%), and SSL (4.7%) suggest good validity of these variables to predict SMLSS. Furthermore, all physiological and biomechanical variables were moderately to highly correlated with S400 (r = .73–.95).

Conclusions:

It is possible to obtain a physiological index of aerobic capacity and performance using simple biomechanical measurements during an incremental test without performing blood lactate analyses.

Restricted access

Kenneth H. Pitetti and Bo Fernhall

The purpose of this study was to evaluate the relationship between aerobic capacity (VO2peak) and leg strength of male (n = 17) and female (n = 12) youths (age = 14.2 ± 2.1 years) with mild to moderate mental retardation. Aerobic capacity was determined by a treadmill test (GXT) and isokinetic knee flexion and extension strength (peak torque, peak force, average force) was determined by isokinetic dynamometry. Results indicate that significant positive relationships (p < .05) exist between VO2peak (ml · min−1 · kg−1) and isokinetic leg strength expressed relative to body weight. The results indicate that leg strength is a contributor to aerobic fitness in youths with mental retardation. Additionally, when considering the low levels of both strength and VO2peak, leg strength may be a limiting factor of VO2peak in these youths, or the relationship may be explained by the concept of metabolic nonspecialization.

Restricted access

Gregory S. Anderson

The purpose of this study was to determine the validity of using the 1600-m distance run (DR) and the maximal multistage 20-m shuttle run (SR) as predictors of aerobic capacity in active boys 10 to 12 years of age. The influence of weight and maximal sprint running speed on test performance scores were also investigated. Both the DR and SR were found to have concurrent validity in the group studied, correlated to a directly measured VO2max (ml kg−1·min−1) determined through a progressive bicycle ergometer test. However, predicted VO2max values using SR results differed significantly from measured values. Weight was not found to be significantly correlated with either of the predictive methods, whereas maximal sprint running speed, as measured through a 40-m dash, was found to correlate significantly with the results of both the DR and SR. These results suggest that the combined influence of running efficiency and anaerobic energy production significantly influence the performance of both predictive methods.

Restricted access

Alison Crosbie

Objective

Asthma is a leading cause of chronic illness in children, impacting heavily on their daily life and participation in physical activity. The purpose of this systematic review was to investigate the evidence for the use of physical therapy to improve pulmonary function and aerobic capacity in children with asthma. Furthermore, the review aims to update previous literature on the effect of exercise on health related quality of life.

Methods

A search was conducted for randomized control trials (RCTs) using the electronic databases Medline, Embase, SPORTDiscus, AMED, CINAHL, and The Cochrane Central Register of Controlled Trials. Studies were included if the participants were asthmatic children aged 6–18 years participating in any mode of physical exercise. Studies were reviewed for study quality, participant details, exercise intervention details, and intervention outcomes.

Results

A total of 16 studies and 516 subjects met inclusion criteria for review. Severity of asthma ranged from mild to severe. No improvement in pulmonary function was observed. Physical training led to an increase in aerobic capacity as measured by VO2max (mL/kg/min).

Conclusions

Findings suggest that physical training does not improve pulmonary function in children with asthma, but does increase aerobic capacity. The small number of studies investigating quality of life suggests that physical training does improve health related quality of life; however further well designed randomized control trials are needed to verify these findings.

Restricted access

Jessica S. West, Tom Ayton, Karen E. Wallman and Kym J. Guelfi

Ingestion of an acute dose of phosphate has been shown to attenuate energy intake in the subsequent meal. This raises the question of whether the practice of phosphate supplementation over a number of days by athletes to enhance performance also influences energy intake. This study investigated the effect of 6 d of phosphate supplementation on appetite and energy intake, as well as aerobic capacity, in trained individuals. Twenty participants completed two 6-d phases of supplementation with either sodium phosphate (50 mg/kg of fat-free mass per day) or a placebo in a double-blinded, counterbalanced design. On Days 1, 2, and 6 of supplementation, a laboratory meal was provided to assess appetite and ad libitum energy intake. All other food and drink consumed during each supplementation phase were recorded in a food diary. After the 6 d of supplementation, peak aerobic capacity (VO2peak) was assessed. There was no difference in energy intake at the laboratory meal after an acute dose (i.e., on Day 1; placebo 2,471 ± 919 kJ, phosphate 2,353 ± 987 kJ; p = .385) or prolonged supplementation with sodium phosphate (p = .581) compared with placebo. Likewise, there was no difference in VO2peak with phosphate supplementation (placebo 52.6 ± 5.2 ml · kg−1 · min−1, phosphate 53.3 ± 6.1 ml · kg−1 · min−1; p = .483). In summary, 6 d of sodium phosphate supplementation does not appear to influence energy intake. Therefore, athletes supplementing with sodium phosphate can do so without hindering their nutritional status. However, given that phosphate supplementation failed to improve aerobic capacity, the ergogenic benefit of this supplement remains questionable.

Restricted access

Dawn T. Gulick and Laurie A. Malone

Edited by Monique Mokha

Restricted access

Ryan D. Burns, James C. Hannon, Timothy A. Brusseau, Patricia A. Eisenman, Pedro F. Saint-Maurice, Greg J. Welk and Matthew T. Mahar

Cardiorespiratory endurance is a component of health-related fitness. FITNESSGRAM recommends the Progressive Aerobic Cardiovascular Endurance Run (PACER) or One mile Run/Walk (1MRW) to assess cardiorespiratory endurance by estimating VO2 Peak. No research has cross-validated prediction models from both PACER and 1MRW, including the New PACER Model and PACER-Mile Equivalent (PACER-MEQ) using current standards. The purpose of this study was to cross-validate prediction models from PACER and 1MRW against measured VO2 Peak in adolescents. Cardiorespiratory endurance data were collected on 90 adolescents aged 13–16 years (Mean = 14.7 ± 1.3 years; 32 girls, 52 boys) who completed the PACER and 1MRW in addition to a laboratory maximal treadmill test to measure VO2 Peak. Multiple correlations among various models with measured VO2 Peak were considered moderately strong (R = .74–0.78), and prediction error (RMSE) ranged from 5.95 ml·kg-1, min-1 to 8.27 ml·kg-1.min-1. Criterion-referenced agreement into FITNESSGRAM’s Healthy Fitness Zones was considered fair-to-good among models (Kappa = 0.31–0.62; Agreement = 75.5–89.9%; F = 0.08–0.65). In conclusion, prediction models demonstrated moderately strong linear relationships with measured VO2 Peak, fair prediction error, and fair-to-good criterion referenced agreement with measured VO2 Peak into FITNESSGRAM’s Healthy Fitness Zones.

Restricted access

Sara López-Martínez, Mairena Sánchez-López, Montserrat Solera-Martinez, Natalia Arias-Palencia, Rosa M. Fuentes-Chacón and Vicente Martínez-Vizcaíno

Purpose:

Our objective was to analyze the association between different intensities of physical activity (PA), physical fitness, and metabolic syndrome (MS) in young adults.

Methods:

Cross-sectional study including 275 university students, 18–30 years old, from Cuenca, Spain. We evaluated (a) physical activity using accelerometry, (b) aerobic capacity (VO2max), and (c) muscle strength, by a muscle strength index calculated as the sum of the standardized z score of handgrip dynamometry/weight and standing broad jump. An MS index was estimated by summing standardized z scores of waist circumference, ratio of triglycerides to high-density lipoprotein, mean arterial blood pressure, and HOMA-IR.

Results:

The mean scores of MS index and HOMAIR were significantly higher and the VO2max significantly lower for individuals who did not perform 20 min or more per week of vigorous physical activity. However, those who performed 250 min/week of moderate physical activity showed no significant differences in either VO2max or the MS index when compared with individuals who did not perform this level of activity. The MS index was lower in those with medium-high levels of aerobic capacity. In addition, individuals with medium-high levels of muscular fitness showed lower waist circumference and a lower MS index.

Conclusions:

VO2max and muscle strength are negatively associated with metabolic risk. 20-min/week of vigorous physical activity was associated with lower cardiometabolic risk in young adults; moderate physical activity did not show association with lower cardiometabolic risk.