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Biomedical subjects

K M Drobish

Publications and source records attributed to K M Drobish.

4 recordsLinked to original sources

Physiological responses to simulated rock climbing at different angles.

PURPOSE: Although rock climbing has increased in popularity as a recreational activity and competitive sport, few studies have assessed the physiological demands of the activity. To describe the physiological responses to rock climbing at different angles. METHODS: Sixteen experienced climbers (age = 26 +/- 8 yr) attempted intermittent climbing bouts at different angles on a special rock climbing treadmill (Brewer's Ledge Treadwall). Heart rate (HR) was monitored continuously, and VO2 was determined at 20-s intervals during each climbing bout. Immediately after each bout, the subject provided a rating of perceived exertion (RPE), and an average of right and left handgrip force (HG) was obtained. Blood was collected via fingerprick after each bout and analyzed for lactate (BL). On a separate day, each subject completed a steady-state treadmill running bout at a HR equal to that obtained at an 86 degree angle during the climbing test. This test was followed by a progression to exhaustion to determine peak HR and VO2 responses. RESULTS: While HR increased with climbing angle, VO2 did not significantly vary. BL began to significantly increase as the angle exceeded vertical (91 degrees) and continued to increase with successive angles. HG decreased with increasing angle and was negatively correlated with BL (r = -0.96). Scores for RPE increased with steeper angles. The comparison of steady-state work at the same HR for climbing versus treadmill running revealed a higher VO2 during running with no differences in BL and RPE. CONCLUSIONS: Based upon these results, it was concluded that continuous rock climbing over terrain steepness of 80 degrees to 102 degrees presents a "very heavy" work challenge, averaging 8.4-9.0 metabolic equivalents, regardless of angle. Despite similar RPE and BL, the relative exercise intensity elicited from simulated rock climbing is lower than that of running at the same HR.

Adult↗

Lactate response to uphill roller skiing: diagonal stride versus double pole techniques.

The purpose of this experiment was to investigate the lactate responses to roller skiing with double pole and diagonal stride techniques in eight collegiate or national level cross-country ski racers. Four-minute exercise stages were performed on a ski treadmill at 67, 94, 121, 148, and 174 m.min-1 on a 1.7% grade and at 67, 94, and 121 m.min-1 on a 7.1% grade. Whole blood lactate concentration, heart rate, oxygen consumption (VO2) and rating of perceived exertion (RPE) were determined at each exercise stage. Blood lactate concentrations were not significantly different between double poling and diagonal striding at the 1.7% grade. However, the blood lactate concentrations were higher during double poling at the 7.1% grade for all speeds. Blood lactate concentrations were also higher for double poling at the 7.1% grade when compared with diagonal striding at 70% of technique specific peak VO2, a heart rate of 145 and a RPE of 12. We conclude that blood lactate concentrations do not offer physiological justification for choosing one technique over the other when skiing on low grades, but low blood lactate concentrations may provide a physiological advantage for diagonal striding on steep grades.

Exercise↗

Physiological comparison of uphill roller skiing: diagonal stride versus double pole.

The physiological responses to treadmill roller skiing with the double pole (DP) and diagonal stride (DS) techniques were compared at 1.7% and 7.1% grades among eight cross-country ski racers. Oxygen uptake (VO2) requirements were found to be lower (P < 0.05) for DP at the 1.7% grade, but similar at the 7.1% grade. In contrast, ratings of perceived exertion (RPE) and percentages of technique-specific peak VO2 were similar between techniques at the 1.7% grade, and lower (P < 0.05) for DS at the 7.1% grade. RPE and percentages of technique-specific peak VO2 were strongly correlated (r = 0.89). The primary findings indicate that 1) the economies for DP and DS are dependent upon the incline, 2) it is possible for the economy of DP to be greater than DS although the percentages of technique-specific peak VO2 are similar, and 3) the perceived effort associated with the use of DP and DS reflects the percentage of technique-specific peak VO2.

Adipose Tissue↗

Physiological responses to specific maximal exercise tests for cross-country skiing.

The present study attempted to quantify differences in peak physiological responses to pole-striding (PS), double poling on roller skis (DP), and diagonal striding on roller skis (DS) during maximal exercise. Six expert cross-country ski racers (3 M, 3 F) with a mean age of 20.2 +/- 1.3 yrs served as subjects. Testing was conducted on a motorized ski treadmill with a tracked belt surface. Expired air was analyzed continuously via an automated open-circuit system and averaged each 20 s. Heart rate was monitored via telemetry and arterialized blood was collected within 1 min of test termination and analyzed immediately for lactate. Peak values for heart rate and blood lactate did not differ among techniques. Peak oxygen uptake was higher for PS and DS versus DP whereas no difference was found between PS and DS. The VO2peak for DP was 77 and 81% of VO2peak for PS and DS, respectively. It was concluded that despite similar peak heart rate and blood lactate values, DP elicits a lower VO2peak than DS or PS and that PS responses appear to closely reflect those of DS.

Adult↗