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A definitive measure for assessing the energy contribution of anaerobic pathways during exhaustive exercise remains inconclusive. The accumulated oxygen deficit (AOD) has been used in several studies to estimate energy contribution. The underlying assumptions of the AOD measure have been criticized for underestimating the true contribution of anaerobic metabolism in high intensity exercise. Indeed, the AOD measure has been the subject of much controversy. Several of the physiological exercise responses of children may lead to an even greater underestimation of the anaerobic energy contribution to high intensity exercise in children than adults when AOD measures are calculated.

The purpose of this study was to determine the anaerobic capacity of children using the maximal accumulated oxygen deficit technique (AOD). Eighteen healthy children (9 boys, 9 girls) with a mean age of 10.6 years volunteered as subjects. Peak oxygen uptake and submaximal steady-state oxygen uptake tests were conducted against progressive constant work rates on a Cybex cycle ergometer. Supramaximal work rates were predicted from the linear regression of submaximal steady-state work rates and oxygen uptakes to equal 110, 130, and 150% of peak oxygen uptake. Results indicated a significant interaction in the responses of both sexes when the accumulated oxygen deficit data were expressed in both absolute and relative terms. The profile of accumulated oxygen deficits across the three intensities indicated a downward shift in the girls responses between the 110 and 150% supramaximal tests. This trend was not evident in the boys’ responses. Intraclass correlations conducted on test-retest data indicated that compared to the boys, the reliability of the girls in the accumulated oxygen deficits in liters and ml·kg⁻¹ was poorer.

Anaerobic characteristics of preadolescent asthmatic and nonasthmatic males were measured using the accumulated oxygen deficit (AOD) on 10 asthmatics (mean age = 10.9 years) and 10 nonasthmatics (mean age = 11.1 years). Subjects ran to exhaustion at speeds that were 110% and 130% of their V̇O₂ peak. Mean AOD values for 110% and 130% were 53.23 ± 4.02 and 50.60 ± 2. 81 ml · kg⁻¹, respectively, for the asthmatic children’s and 51.59 ± 2.66 and 47.04 ± 3.44 ml · kg⁻¹, respectively, for the nonasthmatic children. There were no statistically significant differences in anaerobic characteristics measured by AOD values (p > .05) between intensities and groups. FEV₁ data revealed that there was no bronchoconstriction occurring in either group under either of the test intensity conditions for up to 15 min postexercise.

This study compared tibial bone and muscle geometry and total body and regional bone mineral content (BMC) in elite female adolescent middle-distance runners (n = 20, age: 16 ± 1.7 years) and age- and sex-matched controls (n = 20, 16 ± 1.8 years) using magnetic resonance imaging and dual-energy X-ray absorptiometry. Significant advantages were found in athletes compared with controls in bone and muscle geometric values for distal tibial cortical, medullary cavity, distal tibial total muscle and dorsi flexor muscle compartment cross-sectional area, and regional BMC. Results imply mechanical loads associated with middle-distance running might be beneficial to musculoskeletal health in adolescent females.