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Anita M. Rivera-Brown and Walter R. Frontera

This study examined the effect of different testing ergometers on V̇O2max, V̇O2max criteria achievement, and reliability of V̇O2max for V̇O2 plateau achievers and nonachievers. Twenty trained adolescents completed a treadmill, cycling, and rowing protocol twice. Of all subjects, 35%, 65%, and 45% did not achieve a plateau in either test (No P) during treadmill, cycling, and rowing, respectively. V̇O2max did not differ between tests for the total group or within the plateau and No P groups in any of the ergometers. A high reliability for V̇O2max was obtained in all ergometers. Our data suggest that Taylor’s criterion should not be a requisite for V̇O2max when testing trained adolescents.

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Anita M. Rivera-Brown, Miguel A. Rivera and Walter R. Frontera

This study examined the applicability of criteria for maximal oxygen consumption (V̇O2max) in adolescents. Active females (n=38) and males (n=196) who were students at a sports-technical junior high school performed a treadmill Bruce protocol to volitional fatigue. The criteria for V̇O2max were R ≥1.0, HR ≥95% of predicted maximal for age, and an increase in V̇O2 ≤2.1 ml·kg−1·min−1 with an increase in workload. The first criterion was met by 97% of the females and 93% of the males, while 81% of the females and 75% of the males met the second criterion. Only 8% of the females and 13% of the males met the third criterion. Those who achieved a plateau showed higher HR at peak exercise compared to those who did not (204 ±7.0 vs. 200.6 ±7.2, P≤0.05). Our data indicate that a high proportion of adolescents exhibit subjective and objective indicators of maximal performance without showing a plateau in V̇O2. Age-specific criteria for V̇O2max should be developed.

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Anita M. Rivera-Brown, Miguel A. Rivera and Walter R. Frontera

This study examined the effects of three testing protocols on the frequency of achievement of V̇O2max criteria in 13 male adolescent long-distance runners. All subjects completed the modified Taylor (T), Bruce (B), and Taylor intermittent (TI) running protocols on a treadmill to volitional fatigue. The criteria for V̇O2max were (a) respiratory exchange ratio (R) > 1.0, (b) heart rate (HR) >95% predicted max, and (c) increase in V̇O2 < 2.1 ml·kg−1·min−1 with an increase in workload. A plateau was identified in 54%, 39%, and 85% of the subjects during the T, B, and TI protocols, respectively (p < .05). V̇O2 at exhaustion was similar during all protocols (T = 70.8 ± 4.1, B = 71.4 ± 3.5, TI = 69.6 ± 5.0 ml·kg−1-min−1; p > .05). The data suggest that the characteristics of a protocol can determine the frequency of a plateau achievement but have no effect on the attainment of the R or HR criteria. V̇O2 during running exercise to volitional fatigue is independent of testing protocol.

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Anita M. Rivera-Brown, Miguel A. Rivera and Walter R. Frontera

This study examined the test-retest reliability of V̇O2max in adolescent V̇O2 plateau achievers and nonachievers. Nineteen male long-distance runners completed a modified Taylor running protocol to volitional fatigue twice within a one-week period. Results showed that 10 subjects did not achieve a plateau in either test (No P), and 9 achieved a plateau in at least one of the tests (P). The V̇O2max differed (p < .05) between tests (Test 1 and Test 2) for the entire sample (Test 1 = 70.4 ± 6.0, Test 2 = 71.7 ± 6.3) but not within the groups (No P, Test 1 = 72.1 ± 4.4, Test 2 = 73.2 ± 4.2; P, Test 1 = 68.5 ± 7.3, Test 2 = 70.1 ± 7.9). V̇O2max was similar for plateau achievers and nonachievers in both Test 1 and Test 2 (p > .05). Interclass correlation coefficients for V̇O2max were high for both the No P (R = .87) and P (R = .97) groups. A high test-retest reliability coefficient for V̇O2max can be obtained even when a plateau in V̇O2 is not achieved.

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Michael C. Geraci Jr., Walter Brown and James R. Velasquez

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JesÚs Rico-Sanz, Walter R. Frontera, Paul A. Molé, Miguel A. Rivera, Anita Rivera-Brown and Carol N. Meredith

This study examined the nutritional and performance status of elite soccer players during intense training. Eight male players (age 17 ± 2 years) of the Puerto Rican Olympic Team recorded daily activities and food intake over 12 days. Daily energy expenditure was 3,833 ± 571 (SD) kcal, and energy intake was 3,952 ± 1,071 kcal, of which 53.2 ± 6.2% (8.3 g ⋅ kg BW−1) was from carbohydrates (CHO), 32.4 ± 4.0% from fat, and 14.4 ± 2.3% from protein. With the exception of calcium, all micronutrients examined were in accordance with dietary guidelines. Body fat was 7.6 ± 1.1% of body weight. Time to completion of three runs of the soccer-specific test was 37.65 ± 0.62 s, and peak torques of the knee flexors and extensors at 60° ⋅ s−1 were 139 ± 6 and 225 ± 9 N ⋅ m, respectively. Players' absolute amounts of CHO seemed to be above the minimum recommended intake to maximize glycogen storage, but calcium intakes were below recommended. Their body fat was unremarkable, and they had a comparatively good capacity to endure repeated bouts of intense soccer-specific exercise and to exert force with their knee extensors and flexors.

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Robert M. Beland, Mary Bopp, Andrea Brown, Rosemary Connell, Walter E. Davis, Gary Kamen, Wendell Liemohn, Ruth V. Russell, Stuart Schleien, Paul R. Surburg and Ted Tedrick