Economy and efficiency of human locomotion
- Authors: Goslin, Brian Richard
- Date: 1985
- Subjects: Walking -- Physiological aspects , Running -- Physiological aspects , Human locomotion
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5142 , http://hdl.handle.net/10962/d1007177 , Walking -- Physiological aspects , Running -- Physiological aspects , Human locomotion
- Description: Human locomotor economy and efficiency are highly variable. This study investigated the role that stature plays in this variation, by evaluating metabolic and respiratory responses to walking and running at speeds set relative to one's stature. Four groups of subjects: male, high V0₂ max (n = 11); male, average V0₂ max (n = 10); female, high V0₂ max (n = 10); and female, average V0₂ max (n = 11) were habituated to treadmill locomotion prior to the measurement of maximal oxygen consumption (V0₂ max). The V0₂ max test entailed 1 km.h⁻¹ increases per min from 3 to 6 km.h⁻¹ walking, and 7 - 17 km.h⁻¹ running then 1% grade increments per min until exhaustion. On each of four other occasions, the subject walked or ran at 6 of a variety of relative speeds - walking at 0.5, 0.7, 0.9, 1.1, 1.3; running at 1.5, 1.7, 1.9 and for selected subjects 2.1, 2.3 and 2.5 statures.s⁻¹ ,and grades - 0%, +3%, -3%. Steady-state respiratory and metabolic responses, and treadmill speed were monitored by an on-line computer system developed for this study. Cadence and RPE were also monitored. All subjects demonstrated an exponential relationship between V0₂ and walking relative speed (st.s⁻¹) (RS) . V0₂ (ml.kg⁻¹.min⁻¹ ) = 4.747 * e(1.371*RS) During running this relationship was essentially linear . The variability of economy at relative speed (9.08%) and absolute speed (9. 01%) did not differ. Male and female subjects did not differ in response to absolute speed but females were more economical at relative speeds (p<0.05). Those with high and average aerobic capacity did not differ in locomotor economy at relative speed. Higher freely-chosen stride length was associated with a higher V0₂ response as velocity increased. The V0₂ of uphill walking was 1.4 times greater than that for downhill walking (running: 1.28 times) . Stride length decreased with increasing speed in uphill locomotion but the reverse was the case for downhill. The economy and efficiency of walking was greater than that of running. Walking economy was maximal between 0.7 and 0.9 st. s⁻¹. Running economy remained essentially unaffected by increased velocity. The setting of locomotor velocity relative to stature does not minimize inter-subject variability in metabolic and respiratory response .
- Full Text:
- Date Issued: 1985
- Authors: Goslin, Brian Richard
- Date: 1985
- Subjects: Walking -- Physiological aspects , Running -- Physiological aspects , Human locomotion
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5142 , http://hdl.handle.net/10962/d1007177 , Walking -- Physiological aspects , Running -- Physiological aspects , Human locomotion
- Description: Human locomotor economy and efficiency are highly variable. This study investigated the role that stature plays in this variation, by evaluating metabolic and respiratory responses to walking and running at speeds set relative to one's stature. Four groups of subjects: male, high V0₂ max (n = 11); male, average V0₂ max (n = 10); female, high V0₂ max (n = 10); and female, average V0₂ max (n = 11) were habituated to treadmill locomotion prior to the measurement of maximal oxygen consumption (V0₂ max). The V0₂ max test entailed 1 km.h⁻¹ increases per min from 3 to 6 km.h⁻¹ walking, and 7 - 17 km.h⁻¹ running then 1% grade increments per min until exhaustion. On each of four other occasions, the subject walked or ran at 6 of a variety of relative speeds - walking at 0.5, 0.7, 0.9, 1.1, 1.3; running at 1.5, 1.7, 1.9 and for selected subjects 2.1, 2.3 and 2.5 statures.s⁻¹ ,and grades - 0%, +3%, -3%. Steady-state respiratory and metabolic responses, and treadmill speed were monitored by an on-line computer system developed for this study. Cadence and RPE were also monitored. All subjects demonstrated an exponential relationship between V0₂ and walking relative speed (st.s⁻¹) (RS) . V0₂ (ml.kg⁻¹.min⁻¹ ) = 4.747 * e(1.371*RS) During running this relationship was essentially linear . The variability of economy at relative speed (9.08%) and absolute speed (9. 01%) did not differ. Male and female subjects did not differ in response to absolute speed but females were more economical at relative speeds (p<0.05). Those with high and average aerobic capacity did not differ in locomotor economy at relative speed. Higher freely-chosen stride length was associated with a higher V0₂ response as velocity increased. The V0₂ of uphill walking was 1.4 times greater than that for downhill walking (running: 1.28 times) . Stride length decreased with increasing speed in uphill locomotion but the reverse was the case for downhill. The economy and efficiency of walking was greater than that of running. Walking economy was maximal between 0.7 and 0.9 st. s⁻¹. Running economy remained essentially unaffected by increased velocity. The setting of locomotor velocity relative to stature does not minimize inter-subject variability in metabolic and respiratory response .
- Full Text:
- Date Issued: 1985
Validity and reliability of an objective test of cricket skills
- Authors: Stretch, Richard Aldworth
- Date: 1985
- Subjects: Cricket , Cricket -- Training , Athletic ability -- Testing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5134 , http://hdl.handle.net/10962/d1005625 , Cricket , Cricket -- Training , Athletic ability -- Testing
- Description: This study was conducted to assess the validity and reliability of four self-designed, objective tests of cricket batting, bowling, fielding and general ability skills. The batting test requires the batsman to hit a suspended ball at a target area as many times as possible in 60 seconds. His score is doubled to give his score for the batting test. In the bowling test the bowler is required to bowl ten balls at target areas marked on the pitch. Each delivery is recorded to give him a score out of 100. The fielding test requires the fielder to catch and field seven balls in a predetermined sequence. Each fielded ball that is not thrown through the target area incurs a penalty of three seconds. The total time taken is used to obtain the fielding test score out of 100. In the general ability test the player is required to hit a ball up and down twenty-five times. He then has to run along a predetermined path and field three balls and then bowl three balls at a target. A penalty of three seconds is added onto the time taken for each ball that does not pass through the target area. The actual score, out of 100, is determined from the total time taken. To determine the validity of the objective tests of batting, bowling, fielding and general ability, 155 subjects were subjectively assessed in these four categories by experienced coaches. The four objective tests were then conducted on these subjects and the scores compared. Forty-four subjects were assessed by experienced and inexperienced testers to determine the reliability of the tests when administered by different testers. To determine the reliability of the tests when repeatedly administered by one tester 23 subjects were assessed on five consecutive days. Significant correlations (p < 0,05) were found for the tests of validity between subjective and objective assessment (0,43 to 0,81) and the test for objectivity between experienced and inexperienced testers (0,41 to 0,78). A significant improvement (p < 0,05) in scores occurred during repeated testing, but most of this improvement took place between the first two tests. The results indicate that the tests are valid and reliable tests of cricket batting, bowling, fielding and general ability, if sufficient pre-test practice is allowed.
- Full Text:
- Date Issued: 1985
- Authors: Stretch, Richard Aldworth
- Date: 1985
- Subjects: Cricket , Cricket -- Training , Athletic ability -- Testing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5134 , http://hdl.handle.net/10962/d1005625 , Cricket , Cricket -- Training , Athletic ability -- Testing
- Description: This study was conducted to assess the validity and reliability of four self-designed, objective tests of cricket batting, bowling, fielding and general ability skills. The batting test requires the batsman to hit a suspended ball at a target area as many times as possible in 60 seconds. His score is doubled to give his score for the batting test. In the bowling test the bowler is required to bowl ten balls at target areas marked on the pitch. Each delivery is recorded to give him a score out of 100. The fielding test requires the fielder to catch and field seven balls in a predetermined sequence. Each fielded ball that is not thrown through the target area incurs a penalty of three seconds. The total time taken is used to obtain the fielding test score out of 100. In the general ability test the player is required to hit a ball up and down twenty-five times. He then has to run along a predetermined path and field three balls and then bowl three balls at a target. A penalty of three seconds is added onto the time taken for each ball that does not pass through the target area. The actual score, out of 100, is determined from the total time taken. To determine the validity of the objective tests of batting, bowling, fielding and general ability, 155 subjects were subjectively assessed in these four categories by experienced coaches. The four objective tests were then conducted on these subjects and the scores compared. Forty-four subjects were assessed by experienced and inexperienced testers to determine the reliability of the tests when administered by different testers. To determine the reliability of the tests when repeatedly administered by one tester 23 subjects were assessed on five consecutive days. Significant correlations (p < 0,05) were found for the tests of validity between subjective and objective assessment (0,43 to 0,81) and the test for objectivity between experienced and inexperienced testers (0,41 to 0,78). A significant improvement (p < 0,05) in scores occurred during repeated testing, but most of this improvement took place between the first two tests. The results indicate that the tests are valid and reliable tests of cricket batting, bowling, fielding and general ability, if sufficient pre-test practice is allowed.
- Full Text:
- Date Issued: 1985
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