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Biomedical subjects

R L Seip

Publications and source records attributed to R L Seip.

24 records · Page 2Linked to original sources
PubMed1989

The effects of specificity of training on rating of perceived exertion at the lactate threshold.

To determine the effects of cycle and run training on rating of perceived exertion at the lactate threshold (LT), college men completed a 40-session training program in 10 weeks (n = 6 run training, n = 5 cycle training, n = 5 controls). Pre- and post-training variables were measured during graded exercise tests on both the bicycle ergometer and treadmill. ANOVA on the pre- and post-training difference scores resulted in similar improvements in VO2max for both testing protocols, regardless of training mode. The run training group increased VO2 at the LT by 58.5% on the treadmill protocol and by 20.3% on the cycle ergometer. Cycle trainers increased VO2 LT only during cycle ergometry (+38.7%). No changes were observed in the control group. No differences for RPE at the LT were found before or after training, or between testing protocols for any group. Perception of exercise intensity at the LT ranged from "very light" to "light". The relationship between RPE and %VO2max was altered by the specific mode of training, with trained subjects having a lower RPE at a given %VO2max (no change in RPE at max.). It was concluded that RPE at the LT was not affected by training, despite the fact that after training the LT occurs at a higher work rate and was associated with higher absolute and relative metabolic and cardiorespiratory demands.

Adolescent↗
PubMed1989

Plasma renin activity and albumin excretion in teenage type I diabetic subjects. A prospective study.

Plasma renin activity (PRA) may be high among teenage and young adult insulin-dependent diabetic subjects. Supine PRA and stimulated PRA were therefore measured in 50 female and 50 male diabetic subjects, 13-20 years old, diagnosed before the age of 16. Fifty percent have been restudied after 4.6 +/- 0.2 (mean +/- SEM) years. Initially, 43% had high PRA (supine 4.0 +/- 0.37, stimulated 12.02 +/- 0.8 ng/ml/hr angiotensin I), 45% had normal activity (supine 2.89 +/- 0.26, stimulated 6.47 +/- 0.34 ng/ml/hr/angiotensin I), and 12% had low activity (supine 1.57 +/- 0.05, stimulated 3.09 +/- 0.08 ng/ml/hr/angiotensin I). Levels were directly associated with prepubertal duration of diabetes and were inversely associated with duration of diabetes after onset of puberty but not with total duration or patient age. Within 4.6 +/- 0.2 years the percentage of subjects with high PRA fell to 13%, and the percentage of those with low PRA rose to 35%. Initially 51% of the cohort had normal albumin excretion rates (AER) at rest and during exercise equal to or less than 10 micrograms/min/m2; 32% had elevated rates only during exercise of 39 +/- 5 micrograms/min/m2; 13% had elevated rates at rest of 41 +/- 8 micrograms/min/m2 and during exercise of 116 +/- 21 micrograms/min/m2; and 4% had clinical proteinuria at rest and during each exercise period equal to or greater than 150 micrograms/min/m2. After 5 years, 58% continued to have normal AER, or their AER improved.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Accurate assessment of body composition in obese females.

Although several generalized regression equations exist for body composition assessment the accuracy of these equations for special populations is uncertain. This study examined the ability to predict body composition variables from girth measurements in obese women. Girth measurements were taken on 156 obese women at abdomen 1 and abdomen 2 (mean value of the two was used), buttocks, and right thigh. Stepwise multiple-regression analysis generated on 110 randomly assigned subjects yielded the following equations: density (g/cc) = -0.00020(mean abdomen) - 0.00032(wt) + 0.00039(ht) + 0.97783 (R = 0.76, SEE = +/- 0.00061); % fat = 0.11077(mean abdomen) - 0.17666(ht) + 0.14354(wt) + 51.03301 (R = 0.76, SEE = +/- 2.9); fat wt (kg) = 0.62039(wt) - 0.17844(ht) + 0.09495(mean abdomen) + 5.88874 (R = 0.96, SEE = +/- 2.9); and lean body wt (kg) = 0.37939(wt) + 0.17898(ht) - 0.09494(mean abdomen) - 6.00423 (R = 0.89, SEE = +/- 3.0). Data from the remaining 46 women were used for cross-validation. These equations were valid, with validity coefficients for fat weight and lean body weight of r = 0.92 (SE = +/- 3.3 kg) and r = 0.86 (SE = +/- 3.3 kg), respectively, with no significant mean differences between actual and predicted values. The use of girth measurements is a simple and practical method of estimating fat weight and lean body weight in obese women.

Adult↗
PubMed1985

Absence of left ventricular hypertrophy in elite college basketball players.

Left ventricular dimensions of 11 successful male college basketball players engaged in pre-season conditioning (mean age, 20.3 years) and 13 tall healthy male controls (mean age, 21.6 years) were studied by echocardiography. Left ventricular internal dimension (LVIDd, mm), posterior wall thickness (PWT, mm), septal thickness (ST, mm), and calculated left ventricular mass (LV mass, g) in the athletes were within or only slightly in excess of echocardiographic normal limits and mean values were not significantly different from the control group. LVIDd (mm/m2 body surface area) was significantly lower in the athletes. However, five guard-type players displayed significantly greater mean values for PWT and LV mass compared to six taller forwards/centers with linear body builds. It was concluded that left ventricular hypertrophy is not a common characteristic of college basketball players. It was hypothesized that cardiac dimensions of young men may vary independently of gross body size in relation to somatotype or other anthropometric variables.

Adult↗
PubMed1984

Adrenocortical responses to maximal exercise in moderate-altitude natives at 447 Torr.

Serum hydrocortisone and aldosterone (Aldo) responses to maximal exercise were examined in six low-altitude natives (LAN) (373 m or less, aged 19-25 yr) and eight moderate-altitude natives (MAN) (1,830-2,200 m, aged 19-23 yr) at their residence (home) altitudes (740 and 587 Torr, respectively) and later in a hypobaric chamber at a simulated altitude of 4,270 m (447 Torr). After 2 days at their respective residence altitude and in the chamber, each subject exercised to voluntary exhaustion on the bicycle ergometer. Fluid intake was similar in both groups at all testing locations. Preexercise 24-h urinary Aldo was lower in both groups at 447 Torr but only significantly reduced in the LAN group. In general, the changes in maximum exercise cardiorespiratory variables were twice as large in LAN as in MAN subjects going from residence altitude to 447 Torr. Both serum hydrocortisone and Aldo concentrations were increased (P less than 0.01) after exercise in both groups at residence altitude and 447 Torr. Aldo was lower (P less than 0.05) postexercise at 447 Torr than at residence altitude in both groups, but this decrease was more pronounced (P less than 0.01) in the LAN group. Thus it appears that high-altitude Aldo concentrations are more like resident altitude values in MAN than in LAN subjects.

Acclimatization↗