The purpose of this study was to determine if the regression formula developed for the 20-m shuttle run test (20 MST) for children and adolescents with mild mental retardation (MR), used to predict cardiovascular fitness (V̇O2peak), is valid for adolescents with Down syndrome (DS). Twenty-six adolescents (mean age = 15.3 ± 2.7 yr) with DS (15 males, 11 females) completed a maximal treadmill protocol (measured V̇O2peak) and a 20 MST (predicted V̇O2peak). There was a significant difference (p < .01) between the means of the measured (25.5 ± 5.2 ml·kg-1-·min-1) and the predicted (33.5 ± 3.9 ml·kg-1·min-1) V̇O2peak, respectively. In addition, there was a low relationship between measured and predicted values (r = .54). The results of this study indicate that the regression formula developed for children and adolescents with MR to predict V̇O2peak was not valid in this sample of adolescents with DS.
Myriam Guerra, Kenneth H. Pitetti and Bo Fernhall
Thomas Losnegard, Martin Andersen, Matt Spencer and Jostein Hallén
To investigate the effects of an active and a passive recovery protocol on physiological responses and performance between 2 heats in sprint cross-country skiing.
Ten elite male skiers (22 ± 3 y, 184 ± 4 cm, 79 ± 7 kg) undertook 2 experimental test sessions that both consisted of 2 heats with 25 min between start of the first and second heats. The heats were conducted as an 800-m time trial (6°, >3.5 m/s, ~205 s) and included measurements of oxygen uptake (VO2) and accumulated oxygen deficit. The active recovery trial involved 2 min standing/walking, 16 min jogging (58% ± 5% of VO2peak), and 3 min standing/walking. The passive recovery trial involved 15 min sitting, 3 min walk/jog (~ 30% of VO2peak), and 3 min standing/walking. Blood lactate concentration and heart rate were monitored throughout the recovery periods.
The increased 800-m time between heat 1 and heat 2 was trivial after active recovery (effect size [ES] = 0.1, P = .64) and small after passive recovery (ES = 0.4, P = .14). The 1.2% ± 2.1% (mean ± 90% CL) difference between protocols was not significant (ES = 0.3, P = .3). In heat 2, peak and average VO2 was increased after the active recovery protocol.
Neither passive recovery nor running at ~58% of VO2peak between 2 heats changed performance significantly.
Kenneth H. Pitetti, Bart Jongmans and Bo Fernhall
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.
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.
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.
Jerry Mayo, Brian Lyons, Kendal Honea, John Alvarez and Richard Byrum
Rehabilitation specialists should understand cardiovascular responses to different movement patterns.
To investigate physiological responses to forward- (FM), backward- (BM), and lateral-motion (LM) exercise at self-selected intensities.
Within-subjects design to test independent variable, movement pattern; repeated-measures ANOVA to analyze oxygen consumption (VO2), heart rate (HR), respiratory-exchange ratio (RER), and ratings of perceived exertion (RPE).
10 healthy women.
VO2 and HR were significantly higher during LM than during FM and BM exercise. The respective VO2 (ml · kg · min–1) and HR (beats/min) values for each condition were FM 25.19 ± 3.6, 142 ± 11; BM 24.24 ± 2.7, 145 ± 12; and LM 30.5 ± 4.6, 160 ± 13. No differences were observed for RER or RPE.
At self-selected intensities all 3 modes met criteria for maintaining cardiovascular fitness. Practitioners can use these results to develop rehabilitation programs based on clients’ perception and level of discomfort
Lee N. Burkett, Jack Chisum, Jack Pierce and Kent Pomeroy
Twenty spinal injured wheelchair bound individuals were tested to peak VO2 on a wheelchair ergometer. Sixteen subjects were paraplegics (5 females, 11 males) and four were quadriplegic (2 females, 2 males). The level of injury ranged from C4-5 to L2-3. The mean age of the subjects was 29.9 years, with a mean weight of 63.66 kg. Prior to the peak VO2 and during the rest immediately after peak VO2, each subject was tested for the ability to discriminate touch over the skin of the thigh, leg, and foot. A chi square statistical technique was used to test for differences between pre- and postexercise sensitivity. The chi square was significant at the .003 level of significance. Because the increase in sensitivity was short, it was theorized that under peak exercise stress the body may recruit pathways that have been dormant, but not injured, explaining the increase in sensitivity.
Kenneth H. Pitetti, A. Lynn Millar and Bo Fernhall
The purpose of this study was to compare test-retest reliability when measuring peak physiological capacities of children and adolescents (age = 13.6 ± 2.9 yr) with mental retardation (MR) and their peers (12.0 ± 2.9 yr) without mental retardation (NMR) using a discontinuous treadmill (TM) protocol. Forty-six participants (23 MR = 12 male and 11 female; 23 NMR = 12 male and 11 female) completed two peak performance treadmill tests with 3 to 7 days of rest between tests. Physiological values measured included V̇O2peak (1 $$ min-1 and ml $$ kg-1 $$ min-1), V̇Epeak (1 $$ mhr-1), HRpeak (bpm), and RER (V̇O2 $$ V̇O2 -1). Test-retest reliability coefficients ranged from .85 to .99 for participants with MR and from .55 to .99 for participants without MR. Test reliability and accuracy in the present study does not appear to differ between the NMR and MR participants.
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
Eric D. Vidoni, Anna Mattlage, Jonathan Mahnken, Jeffrey M. Burns, Joe McDonough and Sandra A. Billinger
The purpose of this study was to determine the validity of a submaximal exercise test, the Step Test Exercise Prescription (STEP), in a broad age range and in individuals in the earliest stages of Alzheimer’s disease (AD). Individuals (n = 102) underwent treadmill-based maximal exercise testing and a STEP. The STEP failed to predict peak oxygen consumption (VO2peak), and was a biased estimate of VO2peak (p < .0001). Only 43% of subjects’ STEP results were within 3.5 ml · kg–1 · min–1 of VO2peak. When categorized into fitness levels these 2 measures demonstrated moderate agreement (kappa = .59). The validity of the STEP was not supported in our participants, including those with AD. The STEP may not be appropriate in the clinic as a basis for exercise recommendations in these groups, although it may continue to have utility in classifying fitness in research or community health screenings.