The purpose of this study was to examine the validity and reliability of a treadmill (TM) test for adolescents with multiple disabilities, as defined by PL 105-17. Participants were 16 males and 2 females, ages 11 to 21 (M 14.9 ± 3.2), identified by teachers as potentially able to perform a TM test. Data were collected two times, separated by 2 to 3 weeks. Of the 18 adolescents, 5 could not perform the protocol, and 4 could not complete the test. Intraclass (test–retest) reliability coefficients for HRpeak, V̇Epeak, RERpeak, and V̇O2peak were .90, .90, .88, and .77, respectively, for the remaining 9 participants. Although none of these participants were able to meet the criteria commonly associated for a valid TM maximaltest (V̇O2max), they did meet the criteria for a valid TM maximum test (V̇O2peak) (Wasserman, Hansen, Sue, Whipp, & Casaburi, 1994). Further study of the feasibility of treadmill testing for this population is recommended.
Kenneth H. Pitetti, Bart Jongmans and Bo Fernhall
Amanda J. Griffin, Viswanath B. Unnithan and Peter Ridges
The purpose of this study was to assess the effects of a weekend of swimming competition on various physiological parameters in a group of elite female swimmers. Eight female swimmers (age, 16.6 ± 0.5 years) participated in this study. Resting blood lactate (Bla) and heart rate (HR) were taken at the beginning of each testing session. Testing involved a discontinuous incremental peak VO2 treadmill test during which on-line, measures of VO2 were obtained. HR and Bla measurements were taken at the end of each exercise increment. A 30-s leg Wingate test (WAnT) was used to measure anaerobic power. Paired t-tests were carried out on all data. Resting HR was significantly higher and submaximal and maximal HR were significantly lower comparing pre- and postcompetition (p < .005). Resting Bla and submaximal VO2 were significantly higher postcompetition (p < .005). The results suggest that swimming competition causes a number of the recognized symptoms related to excitatory (acute) overtraining
Bo Fernhall and Kenneth H. Pitetti
This study evaluated the relationship between leg strength and endurance run performance, independent of aerobic capacity (V̇O2peak), body size, and gender, in children and adolescents with mild or moderate mental retardation. Twenty-six individuals (15 boys and 11 girls) volunteered and underwent tests of V̇O2peak, isokinetic leg strength, and endurance run performance (600-yard ran/walk and 20-m shuttle run). Results showed that leg strength was significantly related to both types of run performance; however, when controlling for V̇O2peak, body size, and gender, leg strength was a more significant contributor to the 600-yard run/walk than to 20-m shuttle run performance. Gender did not influence these relationships. These data suggest that leg strength has a significant influence on endurance run performance in children and adolescents with mild or moderate mental retardation.
Han C.G. Kemper, Robbert Verschuur and Langha de Mey
In the Amsterdam Growth and Health Study, 103 girls and 97 boys were studied five times on a longitudinal basis over a period of 8 years, covering the teenage years from 12 to 17 until young adulthood at 22/23 years. Measured were anthropometric variables such as height, weight (BW), and body fat, and physiological variables such as maximal aerobic power (V̇O2max) and endurance performance (max slope). During the teenage period, V̇O2max/BW remains constant in boys and decreases in girls whereas endurance performance increases in boys and remains constant in girls. By young adulthood V̇O2max/BW and maximal slope have declined in both sexes, and in the case of females are even lower than at the beginning of their teens. Boys superiority in aerobic fitness and the decline in aerobic fitness in both sexes is mainly caused by the differences in the intensity of daily physical activity level.
Dale I. Lovell, Ross Cuneo and Greg C. Gass
This study examined the effect of aerobic training on leg strength, power, and muscle mass in previously sedentary, healthy older men (70–80 yr). Training consisted of 30–45 min of cycle ergometry at 50–70% maximal oxygen consumption (VO2max), 3 times weekly for 16 wk, then 4 wk detraining, or assignment to a nontraining control group (n = 12 both groups). Training increased leg strength, leg power, upper leg muscle mass, and VO2max above pretraining values (21%, 12%, 4%, and 15%, respectively; p < .05). However, all gains were lost after detraining, except for some gain in VO2max. This suggests that cycle ergometry is sufficient stimulus to improve neuromuscular function in older men, but gains are quickly lost with detraining. For the older population cycle ergometry provides the means to not only increase aerobic fitness but also increase leg strength and power and upper leg muscle mass. However, during periods of inactivity neuromuscular gains are quickly lost.
Claire F. Fitzsimons, Carolyn A. Greig, David H. Saunders, Susan J. Lewis, Susan D. Shenkin, Cynthia Lavery and Archie Young
This study examined the effect of age on descriptive walking-speed instructions commonly used in health promotion. Participants were 9 young (20–23 years) and 9 older (75–83 years) women. Oxygen uptake and walking speed were measured in response to descriptive walking instructions (“slow,” “comfortable,” “brisk,” and “fast”). Although the older women walked ≈20% slower in response to all walking instructions and with significantly lower oxygen costs for brisk and fast, the intensity of the exercise represented a much greater percentage of VO2max and showed greater interindividual variation. When asked to walk at a brisk pace, the older women averaged 67% VO2max (SD 20.6), whereas the young women averaged only 45% VO2max (SD 4.5). With older people, brisk might elicit an exercise intensity unnecessarily high for physiological benefit and that might compromise safety and adherence, which emphasizes the need for validation of carefully worded exercise and training guidance for older adults.
Kelly S. Chu, Edward C. Rhodes, Jack E. Taunton and Alan D. Martin
The purpose of this study was to assess the difference in maximal physiological responses between an acute bout of deep-water running (DWR) and treadmill running (TMR) in young and older adults. Participants were 9 young and 9 older women who performed maximal DWR and TMR tests. Maximal measures included oxygen consumption (VO2max), heart rate (HRmax), ventilation (VE), respiratory-exchange ratio (RER), and blood lactate (BLac). The young women exhibited higher VO2max, HRmax, VE, and BLac than did the older women for both exercise conditions (p < .05). Lower VO2max and HRmax values were observed with DWR for both age groups (p < .05). No significant differences were found for VE, RER, and BLac in either group between exercise conditions, nor a significant interaction between exercise conditions or ages for any of the variables measured. The data suggest that although older adults exhibit lower maximal metabolic responses, differences between DWR and TMR responses occur irrespective of age.
Nobuo Takeshima, Masatoshi Nakata, Fumio Kobayashi, Kiyoji Tanaka and Michael L. Pollock
The purpose of this study was to determine the effects of head-out-of-water immersion (HOI) on elderly subjects’ heart rate (HR) and oxygen uptake (V̇O2) responses to graded walking exercise. Subjects were 15 elderly participants. who selected three walking speeds and exercised for 6 min at each intensity on land and in the water. HOI exercise was carried out with subjects immersed to the level of the axilla. HR response at a given V̇O2 during walking with HOI was similar to the values found for walking on land, in contrast to published data on young subjects. The findings are consistent with the hypothesis that water immersion-induced central redistribution of blood volume changes with advancing age and may lead to a difference in the HR–V̇O2 relationship during HOI walking in the elderly compared to the young. This has important implications for prescribing exercise to the elderly when using treadmill HR values for HOI walking training.
Andrew S. Cole, Megan E. Woodruff, Mary P. Horn and Anthony D. Mahon
Relationships between physiological parameters and 5-km running performance were examined in 15 male runners (17.3 ± 0.9 years). Running economy (RE) and blood lactate concentration ([BLa]) at 241.2 m/min, VO2max, velocity at VO2max (vVO2max), vertical jump height and muscle power, and isokinetic knee extension strength at 60°/sec and 240°/sec were measured. The participants’ best 5-km race time over the last month of the cross-country season (16.98 ± 0.76 min) was used in the analysis. The data were analyzed using Pearson correlation coefficients. Significant relationships to run time were observed for VO2max (r = -.53), RE (r = .55), and vVO2max (r = -.66), but not [BLa], isokinetic muscle torque, or vertical jump. Identifying the unique strength and power characteristics related to running performance in this age group is warranted.
Fagner Serrano, Jana Slaght, Martin Sénéchal, Todd Duhamel and Danielle R. Bouchard
Many international agencies recommend using 40% of VO2reserve to individually prescribe moderate aerobic intensity to achieve health benefits. Few studies have evaluated the walking cadence needed to reach that intensity for older adults. A total of 121 apparently healthy adults with an average age of 69 and an average VO2peak of 24.1 ± 6.7 ml/kg/min (women) and 28.9 ± 9.1 ml/kg/min (men) were studied. Walking cadence at moderate intensity was established when participants reached 40% of VO2reserve on an indoor flat surface using a portable metabolic cart. Other clinical variables potentially associated with walking cadence were collected to create a clinical algorithm. Mean walking cadence to reach moderate intensity was 115 ± 10 steps per minute. The best algorithm to predict the walking cadence needed to reach moderate intensity in this sample was 113.6–0.23 (body weight in kg) + 0.21 (self-selected walking cadence in steps per minute).