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J M Rippe

Publications and source records attributed to J M Rippe.

10 recordsLinked to original sources
PubMed1992

Treadmill validation of an over-ground walking test to predict peak oxygen consumption.

The purpose of this study was to determine whether a test developed to predict maximal oxygen consumption (VO2max) during over-ground walking, was similarly valid as a predictor of peak oxygen consumption (VO2) when administered during a 1-mile (1.61 km) treadmill walk. Treadmill walk time, mean heart rate over the last 2 full min of the walk test, age, and body mass were entered into both generalized (GEN Eq.) and gender-specific (GSP Eq.) prediction equations. Overall results indicated a highly significant linear relationship between observed peak VO2 and GEN Eq. predicted values (r = 0.91), a total error (TE) of 5.26 ml.kg-1.min-1 and no significant difference between observed and predicted peak VO2 mean values. The peak VO2 for women (n = 75) was predicted accurately by GSP Eq. (r = 0.85; TE = 4.5 ml.kg-1.min-1), but was slightly overpredicted by GEN Eq. (overall mean difference = 1.4 ml.kg-1.min-1; r = 0.86; TE = 4.56 ml.kg-1.min-1). No significant differences between observed peak VO2 and either GEN Eq. (r = 0.85; TE = 4.3 ml.kg-1.min-1) or GSP Eq. (r = 0.85; TE = 4.8 ml.kg-1.min-1) predicted values were noted for men (n = 48) with peak VO2 values less than or equal to 55 ml.kg-1.min-1. However, both equations significantly underpredicted peak VO2 for the remaining high peak VO2 men (n = 22). In conclusion, the over-ground walking test, when administered on a treadmill, is a valid method of predicting peak VO2 but underpredicts peak VO2 of subjects with observed high peak VO2 values.

Adult↗
PubMed1992

Athletic heart syndrome.

AHS is a benign condition consisting of physiologic adaptations to the increased cardiac work load of exercise. Its primary features are biventricular hypertrophy and bradycardia associated with normal systolic and diastolic function. In addition, the alterations in cardiac structure are related to the type of training with dynamic training causing proportionally greater dilation and static training primarily increased wall thickness. AHS is associated with abnormalities in ECG, radiograph, and echocardiographic findings. It is important to be aware of these changes so that they are not misinterpreted to represent pathologic states. In particular, the distinction between AHS and HCM can be difficult, although certain historic and echocardiographic features can help differentiate the two.

Animals↗
PubMed1991

Estimation of VO2max: a comparative analysis of five exercise tests.

Thirty-eight female subjects (M +/ SD = 33 +/- 3.0 years) had VO2max measured on the cycle ergometer (M +/- SD = 37.3 +/- 6.4 ml.kg-1.min-1) and on the treadmill (M +/- SD = 41.3 +/- 6.6 ml.kg-1.min-1). VO2max was estimated for each subject from heart rate (HR) at submaximal workloads on the cycle ergometer using the Astrand-Rhyming nomogram (A/R) and the extrapolation method (XTP). VO2max was also estimated from three field tests: 1.5-mile run (RUN) (independent variable [IV] = time), mile walk (WALK) (IV = time, age, HR, gender, body weight), and the Queens College Step Test (ST) (IV = HR during 5-20 s recovery). Repeated measure ANOVA revealed significant mean differences between the criterion cycle ergometer VO2max versus A/R and XTP (20 and 12% overestimation). The WALK, RUN, and ST VO2max values were not significantly different from the criterion treadmill VO2max. The correlation between criterion VO2max estimated from the WALK and RUN were r = .73 (SEE = 4.57 ml,kg-1.min-1) and r = .79 (SEE = 4.13 ml.kg-1.min-1), respectively. The ST, A/R, and XTP had higher SEEs (13-13.5% of the mean) and lower r s (r = .55 to r = .66). These results suggest both the WALK and RUN tests are satisfactory predictors of VO2max in 30 to 39-year-old females.

Adult↗
PubMed1991

Development of a single-stage submaximal treadmill walking test.

An equation was developed to estimate maximal oxygen uptake (VO2max, ml.kg-1.min-1) based on a single submaximal stage of a treadmill walking test. Subjects (67 males, 72 females) aged 20-59 yr completed 4-min stages at 0, 5, and 10% grades walking at a constant speed (2.0-4.5 mph) and then performed a VO2max test. Heart rate and respiratory gas exchange variables were measured during the test. Multiple regression analysis (N = 117) to estimate VO2max from the 4-min stage at 5% grade yielded the following model (R2 = 0.86; SEE = 4.85 ml.kg-1.min-1): VO2max = 15.1 + 21.8*SPEED (mph) -0.327*HEART RATE (bpm) -0.263*SPEED*AGE (yr) + 0.00504*HEART RATE*AGE + 5.98*GENDER (0 = Female; 1 = Male). The constant and all coefficients were highly significant (P less than 0.01). To assess the accuracy of the model in a cross-validation group (N = 22), an estimated VO2max value was obtained using the above model. Estimated VO2max then was regressed on observed VO2max yielding the following equation (R2 = 0.92): ESTIMATED VO2max = 0.15 + 1.03*OBSERVED VO2max. The intercept and slope of this equation were not significantly different from 0 and 1, respectively. For 90.9% of the subjects in the cross-validation group, residual scores were within the range of +/- 5 ml.kg-1.min-1. In conclusion, this submaximal walking test based on a single stage of a treadmill protocol provides a valid and time-efficient method for estimating VO2max.

Adult↗
PubMed1988

Walking for health and fitness.

Recent studies have linked regular physical activity with reduced likelihood of developing coronary heart disease. Even low- and moderate-intensity exercise such as walking, when carried out consistently, is associated with important cardiovascular health benefits. Walking has also been shown to reduce anxiety and tension and aid in weight loss. Regular walking may help improve cholesterol profile, help control hypertension, and slow the process of osteoporosis. Recent physiological studies have demonstrated that brisk walking provides strenuous enough exercise for cardiovascular training in most adults. A recently developed submaximal 1-mile walk test provides a simple and accurate means for estimating aerobic capacity and guiding exercise prescription. These new insights and tools will assist the clinician in the prescription of safe and effective walking programs.

Coronary Disease↗
PubMed1987

Estimation of VO2max from a one-mile track walk, gender, age, and body weight.

The purpose of this investigation was to explore an alternative field test to estimate maximal oxygen consumption (VO2max) using a one-mile walk test. VO2max was determined in 343 healthy adult (males = 165, females = 178) subjects 30 to 69 yr using a treadmill protocol (mean +/- SD: VO2max = 37.0 +/- 10.7 ml X kg-1 X min-1). Each subject performed a minimum of two, one-mile track walks as fast as possible. The two fastest walks (T1, T2) with elapsed times within 30 s were used for subsequent analyses. Heart rates were monitored continuously and recorded every one-quarter mile. Multiple regression analysis (best sub-sets) to estimate VO2max (l X min-1) yielded the following predictor variables: track walk-1 time (T1); fourth quarter heart rate for track walk-1 (HR 1-4); age (yr); weight (lb); and sex (1 = male, 0 = female). The best equation (N = 174) was: VO2max = 6.9652 + (0.0091*WT) - (0.0257*AGE) + (0.5955*SEX) - (0.2240*T1) - (0.0115*HR1-4); r = 0.93, SEE = 0.325 l X min-1. Comparing observed and estimated VO2max values in a cross-validation group (N = 169) resulted in r = 0.92, SEE = 0.355 l X min-1. Generalized and sex-specific equations to estimate VO2max (ml X kg-1 X min-1) were also generated. The accuracy of estimation as expressed by SEE was similar among the equations. The results indicate that this one-mile walk test protocol provides a valid sub-maximum assessment for VO2max estimation.

Adult↗
PubMed1979

Multiple floppy valves: an echocardiographic syndrome.

Echocardiograms of 400 patients with mitral valve prolapse examined at the Peter Bent Brigham Hospital between 1974 and 1977 were reviewed. Eleven patients (3 per cent) were found to have prolapse (10 patients) or large excursion of the tricuspid valve (one patient) and large excursion of the aotric valve (four patients) or dilatation of the aotric root (seven patients) in addition to mitral valve prolapse. Two of these 11 patients underwent mitral valve replacement, and myxomatous degeneration of the valves was noted on pathologic examination. Almost half of the patients with multiple floppy valves (five of 11) had symptoms of congestive heart failure. In contrast to reported series of isolated mitral valve prolapse, in which female preponderance has been documented, 10 of the 11 patients were male. The syndrome of multiple floppy valves may represent either a unique entity or a more advanced form of the same process which underlies mitral valve prolapse.

Adult↗
PubMedDate not supplied

Hemodynamics and left ventricular function: a comparison between adult racing greyhounds and greyhounds completely untrained from birth.

Trained racing greyhounds are known to have cardiomegaly, higher mean arterial pressure and cardiac indices and lower systemic arterial resistances at rest than mongrel dogs. In order to distinguish between those hemodynamic and left ventricular functional characteristics that are inborn in the greyhound as opposed to those which are acquired through training, we studied 9 adult (mean age 22.9 +/- 4.2 [S.D.] months) trained racing greyhounds within 8 days of the cessation of training and 9 adult greyhounds raised under sedentary conditions (mean age 21.7 +/- 1.4 months). Seven healthy adult mongrel dogs served as additional controls. Right and left heart catheterizations of chloralose-anesthetized animals included hemodynamic and left ventricular functional measurements before and after volume loading with 500 ml 6% dextran in normal saline. Heart weight/body weight ratios were the same in both trained and untrained greyhounds, favoring the concept that the cardiomegaly of greyhounds is genetic and not acquired. Trained greyhounds had significantly decreased systemic vascular resistance, increased cardiac index and stroke volume, and a tendency (non significant) toward elevated systemic arterial pressure in comparison to mongrels. Life-long untrained adult greyhounds had hemodynamic measurements that did not differ from mongrels; they also had significantly higher systemic vascular resistances and lower cardiac indices than trained greyhounds. Some hemodynamic characteristics of the trained adult greyhound dog are not present in completely untrained greyhounds and are the result of either training alone or training superimposed on genetic predisposition.

Animals↗