Browsing by Author "Cicone, Zackary S."
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item Cross-Validation of Age-Based Maximal Heart Rate Equations in Youth Soccer Players(2017) Cicone, Zackary S.; Holmes, Clifton J.; Liu, Yuan; Sherman, Sara; Esco, Michael R.PROBLEM: Maximal heart rate (MHR) can be an important reference for prescribing aerobic exercise intensity in athletes. While many prediction equations are available to estimate MHR, few of them have been validated in adolescent athletes. PURPOSE: The purpose of this study was to compare the differences between laboratory-measured and age-predicted MHR in youth athletes. METHODS: Thirty adolescent male soccer players volunteered to participate in this study. Subjects performed a maximal graded exercise test until volitional fatigue. The highest heart rate achieved during the test was recorded. Age-predicted MHR was calculated for each subject using equations by Fox, Tanaka, Shargal, and Nikolaidis. Measured and predicted MHR values were compared using within-subjects analysis of variance. Bias and limits of agreement (CE ± 1.96 SD) were calculated using the Bland-Altman method. RESULTS: There were no significant differences between MHR and age-predicted MHR from the Fox equation. The Tanaka, Shargal, and Nikolaidis equations significantly under-predicted MHR when compared to the criterion. CE ± 1.96 SD was 0.4 ± 15.0 for Fox, -7.2 ± 15.0 for Tanaka, -8.6 ± 15.1 for Shargal, and -3.0 ± 15.1 for Nikolaidis. CONCLUSIONS: The results of the study showed that there were significant mean differences between three age-prediction equations (i.e., Tanaka, Shargal, and Nikolaidis) and actual MHR. Even though the MHR values derived from the Fox equation were not significantly different from the criterion, there was a large range of individual differences that make its application limited. Therefore, age-predicted MHR equations in youth athletes should be used with caution.Item Field-Based Performance Tests Are Related to Body Fat Percentage and Fat-Free Mass, But Not Body Mass Index, in Youth Soccer Players(MDPI, 2018) Esco, Michael R.; Fedewa, Michael, V; Cicone, Zackary S.; Sinelnikov, Oleg A.; Sekulic, Damir; Holmes, Clifton J.; University of Alabama Tuscaloosa; University of SplitThe primary aim of this study was to determine the association between body composition and performance outcomes in youth soccer players. Twenty-five competitive male youth soccer players (age = 13.7 +/- 0.8 years, height = 167.4 +/- 9.7 cm, weight = 57.6 +/- 12.1 kg) volunteered to participate in this study. Height and weight were used to calculate body mass index (BMI). Body fat percentage (BF%) and fat-free mass (FFM) were determined with dual-energy X-ray absorptiometry. Each athlete performed the Pacer test, vertical jump, and t-test drill. Participants were predominantly normal weight (20.4 +/- 2.7 kg.m(-2)). The body composition results were 20.3 +/- 4.9% for BF% and 46.5 +/- 8.7 kg for FFM. The results of the performance tests indicated a mean standard deviation (SD) of 1418 +/- 332 m for Pacer, 57.2 +/- 7.4 cm for vertical jump, 11.6 +/- 0.7 s for t-test. Body mass index was not associated with any performance measure (r = 0.02 to -0.21, all p > 0.05). Body fat percentage was associated with the Pacer, vertical jump, and t-test (r = -0.62, -0.57, 0.61, respectively; all p < 0.01) and remained after accounting for BMI. Fat-free mass was only significantly related to t-test (r = -0.43, p < 0.01). However, after controlling for BMI, FFM was related to all three performance tests. Body fat percentage and FFM are associated with performance in youth soccer players, with stronger relationships reported in the former metric. The findings highlight the need for accurate body composition measurements as part of an assessment battery in young athletes.Item Generalized Equations for Predicting Percent Body Fat from Anthropometric Measures Using a Criterion Five-Compartment Model(Lippincott Williams & Wilkins, 2021) Cicone, Zackary S.; Nickerson, Brett S.; Choi, Youn-Jeng; Holmes, Clifton J.; Hornikel, Bjoern; Fedewa, Michael, V; Esco, Michael R.; Shenandoah University; University of Alabama Tuscaloosa; Texas A&M International University; Ewha Womans University; Washington University (WUSTL)Introduction: Anthropometric-based equations are used to estimate percent body fat (%BF) when laboratory methods are impractical or not available. However, because these equations are often derived from two-compartment models, they are prone to error because of the assumptions regarding fat-freemass composition. The purpose of this study was to develop a new anthropometric-based equation for the prediction of%BF, using a five-compartment (5C) model as the criterion measure. Methods: A sample of healthy adults (52.2% female; age, 18 to 69 yr; body mass index, 15.7 to 49.5 kg.m(-2)) completed hydrostatic weighing, dual-energy x-ray absorptiometry, and bioimpedance spectroscopy measurements for calculation of 5C%BF (%BF5C), as well as skinfolds and circumferences.%BF5C was regressed on anthropometric measures using hierarchical variable selection in a random sample of subjects (n = 279). The resulting equation was cross-validated in the remaining participants (n = 78). New model performance was also comparedwith several common anthropometric-based equations. Results: The new equation [%BFNew = 6.083 + (0.143 x SSnew) - (12.058 x sex) - (0.150 x age) - (0.233 x body mass index) + (0.256 x waist) + (0.162 x sex x age)] explained a significant proportion of variance in %BF5C (R-2 = 0.775, SEE = 4.0%). Predictors included sum of skinfolds (SSnew, midaxillary, triceps, and thigh) and waist circumference. The new equation cross-validated well against %BF5C when compared with other existing equations, producing a large intraclass correlation coefficient (0.90), small mean bias and limits of agreement (0.4% +/- 8.6%), and small measures of error (SEE = 2.5%). Conclusions: %BFNew improved on previous anthropometric-based equations, providing better overall agreement and less error in %BF estimation. The equation described in this study may provide an accurate estimate of %BF5C in healthy adults when measurement is not practical.