Table of Contents
Physical Education Teacher Education Leaders’ Perceptions on a National Curriculum in Physical Education
– Junghwan Oh and Kim C. Graber
Given criticism of P-12 physical education and wide variability in instructional quality and subject matter outcomes in the United States (US), a national curriculum has been debated by some scholars as a mechanism for improving the status of the subject matter. Grounded in the systemic reform (SR) model, the purpose of this study was to explore physical education teacher education (PETE) leaders’ perceptions regarding the implementation of a national curriculum.
In total, 28 individuals participated in in-depth interviews that were inductively/deductively coded and triangulated.
Themes indicated that nationalizing the curriculum has the potential to offer explicit educational goals, substantial pedagogical guidelines, and valid assessments. Despite recognizing the potential benefits of national curriculum, however, the majority of participants were opposed because of the inflexibility of such a system in the culturally and geographically diverse school contexts across the US.
The concept of national curriculum can be differently interpreted in different countries based on sociocultural, historical, and contextual factors, and its relevance depends primarily on one’s perceptions and previous experiences.
Examining the Pathway to Motor Skill Competence in a Mastery Motivational Climate: An Appreciative Inquiry
– Peter A. Hastie, Mary E. Rudisill, Korey Boyd, and Jerraco L. Johnson
Purpose: This study followed a strengths-based approach to identify the pathway children follow as they develop from novice to skillful learners during a mastery-motivational physical education setting.
The Absolute and Relative Reliability of Psychophysiological Responses to Self-Selected Exercise Intensity in Elderly Women
Method: Eleven 4-year-old children (nine boys) participated in a motor activity program delivered twice weekly across 26 weeks. The teacher participated in monthly 30–45-min interviews that sought to identify the critical moments of the program as it had progressed to that point in time. Photographic images of the children’s experiences in the climate acted as prompts during interviews. Interview transcripts were subject to a deductive analysis in which the ideas of “what was working well” and “what the future might look like” were the initial categories.
Results: Interview and photo analyses revealed that the children moved through three phases on their pathway towards mastery. In phase 1, “captivation” and “exploration,” the children presented the teacher with challenges in developing the managerial system. In phase 2, “cooperation” and “consolidation,” there was significantly less task modification and more time in deliberate practice. In phase 3, “dedication” and “collaboration,” the children began to actively seek out the teacher as a resource to help them learn.
Conclusion: The identification of critical teaching behaviors during the program adds support for our contention that the teacher is a critical component in helping children advance along the pathway of mastery when placed in an autonomy-supportive climate. These are allowing time for exploration and experiencing freedom, adding structure, and helping students learn to manage themselves.
– Ozeas L. Lins-Filho, Tony M. Santos, Raphael M. Ritti-Dias, Vinícius O. Damasceno, and Daniela K. S. Ferreira
Purpose: To evaluate the test-retest reliability and the minimum detectable change of the perceptive and physiological responses in two sessions of SSEI on treadmill in elderly women.
Feedforward Self-Modeling and Self-Regulation: It’s Not Just for Learning
Method: Twenty elderly women (ages 65.3 ± 4.2 years) performed two 20-min laboratory-based treadmill aerobic exercise sessions with self-selected intensity. During the sessions, %VO2max, %HRreserve, affect, and rating of perceived exertion (RPE) were recorded. Reliability was calculated using the intraclass correction coefficient (ICC) and Bland–Altman plots. The minimum detectable change (MDC) was also calculated.
Results: ICC values were 0.98 for % VO2max, 0.83 for % HRreserve, 0.85 for affect, and 0.80 for RPE. No differences were observed in mean values between sessions for all the variables. MDCs were lower than 0.7% for VO2max, 11.7% for HRreserve, 0.7 for affect, and 0.8 for RPE. Bland–Altman plots showed a bias of 0.50% for HRreserve, 3.2% for VO2max, 0.05 for affect, and −0.35 for RPE.
Conclusion: Self-selected intensity during aerobic exercise performed on treadmill is reliable, which promotes adequate and lower MDC values on physiological and perceptual responses in elderly women.
– Amanda M. Rymal and Diane M. Ste-Marie
Purpose: This research investigated whether Zimmerman’s model of self-regulated learning could be transferred into a competitive setting. We also investigated whether a feedforward self-modeling video could influence one’s use of self-regulation and as such be an effective self-regulatory intervention.
Comparison of 2- and 3-Minute Inter-Repetition Rest Periods on Maximal Jerk Technique and Power Maintenance
Method: Nine competitive gymnasts took part in two interviews; one interview was conducted after a competition in which the video was viewed (experimental interview: EI) and the other after a competition where no video was seen (control interview: CI).
Results: The gymnasts’ responses to the interviews suggested that many processes and beliefs used in the learning context described by Zimmerman were also engaged in within a competitive context. Furthermore, comparison of gymnasts’ responses between the EI and CI suggested that the feedforward self-modeling video influenced gymnasts’ use of self-regulation during a competition.
Conclusion: This research suggests that Zimmerman’s model of self-regulation has potential to be transmitted into the competitive context and that an individual’s self-regulation can be influenced by viewing a feedforward self-modeling video.
– Achraf Ammar, Bryan L. Riemann, Khaled Trabelsi, Marcel Blaumann, Osama Abdelkarim, Hamdi Chtourou, Tarak Driss, and Anita Hökelmann
Purpose: The aim of this study was to examine the effect of 3- vs. 2-minute inter maximal-repetition rest period (IMRRP) on maintaining jerk technical efficiency and power production during two successive maximal repetitions of Clean & Jerk (C&J).
Reliability of Teams’ Game-Related Statistics in Basketball: Number of Games Required and Minimal Detectable Change
Method: In a randomized, within subject, repeated measures design, nine elite-weightlifters (age: 24.4 ± 3.6 years, body mass: 77.2 ± 7.1 kg, height 176.0 ± 6.4 cm and 1RM C&J: 170.0 ± 5.0 kg) performed 2-separate testing sessions using 2 (IMRRP-2) and 3 (IMRRP-3) -minute IMRRP, while barbell kinematics and kinetics and joint kinematics were recorded.
Results: Statistical analysis showed that one minute longer IMRRP enhanced the maintenance of optimal jerk technique evidenced by reducing declines in peak vertical barbell displacement (2.74%; p = .03), peak barbell velocity (2.89%; p = .03), and peak knee (1.61%; p = .03) and hip extensions (1.59%; p = .03) during the drive phase of the jerk. Additionally, IMRRP-3 led to maintaining optimal lifting strategy by reducing the increase in horizontal displacement during the descending (3.85%; p = .04) and ascending (5.42%; p = .02) phases. Increasing IMRRP from 2min to 3min was also shown to enhance kinetic variables evidenced by prompting higher peak vGRF (2.01%; p = .04) and power (2.55%; p = .04).
Conclusion: To better identify an athlete’s maximal jerk technique and power maintenance, the results of this study suggest 3min as more appropriate IMRRP during successive C&J at 100% 1RM.
– Alexandra Pérez-Ferreirós, Anton Kalén, Miguel-Ángel Gómez, and Ezequiel Rey
Purpose: Analyze the number of games required to obtain a good relative and absolute reliability of teams’ game-related statistics.
Physiological Differences Between Heat Tolerant and Heat Intolerant Young Healthy Women
Method: A total of 884 games from the 2015–2016 to 2017–2018 seasons of the Spanish men’s professional league were analyzed using all games and clustered by scoring difference. Intra-class correlation coefficient (ICC) was calculated for each variable. The number of games required to detect a change and to achieve good relative reliability was calculated using minimal detectable change and Spearman-Brown prophecy formula respectively.
Results: Using all games, the results showed that the minimal number of games required in each group was 30 to detect a medium change (d > .5), 187 for a small change (d > .2), and 100 for good relative reliability (ICC ≥ .75). Using balanced and unbalanced games, the minimal number of games required in each group was respectively 31 and 30 to detect a medium change (d > .5), 190 and 188 for a small change (d > .2), and 191 and 121 for good relative reliability (ICC ≥ .75).
Conclusion: The sample needs to consist of at least 30 games in each group to detect a medium size change, and at least 190 games to detect a small size change. To be able to rank teams with good reliability, at least 100 games are required when including both balanced and unbalanced games.
– Ran Yanovich, Itay Ketko, Jeni Muginshtein-Simkovitch, Einat Yanovich, Uri Eliyahu, Chen Fleischmann, Danit Atias-Varon, Barliz Waissengrin, Chen Makranz, and Yuval Heled
Purpose: Heat intolerance (HI) is determined in the Israel Defense Force according to a heat tolerance test (HTT) before returning to duty after an exertional heat stroke (EHS) event. Recently, increased numbers of female combatants resulted in an increased number of EHS cases among women and a higher percentage of heat intolerance (HI) individuals. We aimed to evaluate the differences between tolerance to heat among women performing an HTT in relation to their menstrual cycle phase.
Effects of the Menstrual Cycle on Running Economy: Oxygen Cost Versus Caloric Cost
Method: Thirty-three female participants were sorted into two groups: HI and heat tolerant (HT) according to two HTTs performed during both the luteal and follicular phases of the menstrual cycle or while consuming and during a break from consuming contraceptives.
Results: HT women had an 18% higher maximal oxygen uptake (p < .005, 95% CI (2.6,9.8)) and 1.2% lower skin temperature in the HTT at the during and follicular phases (p < .01, 95% CI (0.12,0.77)) and 1.7% lower at the off and luteal phases (p < .001, 95% CI (0.34,0.92)). The mean sweat rate was 14% lower among the HI group only at the HTT at the during and follicular phases (p < .05, 95% CI (3,88))).
Conclusion: We found that HT can be predicted using aerobic capacity and core body temperature. Moreover, during the luteal phase, women presented altered thermoregulation that decreased the probability of being HT. This emphasizes the importance of considering the HT/HI criteria in the HTT for women, according to their aerobic ability and menstrual-cycle phase.
– Bircan Dokumacı and Tahir Hazır
Purpose: This study investigated the effects of the menstrual cycle on running economy (RE).
Individualized Accelerometer Activity Cut-Points for the Measurement of Relative Physical Activity Intensity Levels
Method: Eleven eumenorrheic female athletes (mean age: 21.18 ± 3.65 years, height: 170.2 ± 6.6 cm, VO2max: 49.25 ± 9.15 mL·kg−1·min−1, and menstrual cycle: 29.8 ± 0.98 days) were tested for anthropometric variables, physiological responses (oxygen consumption (VO2), blood lactate (LA), heart rate (HR), and respiratory exchange ratio (RER)) at rest and while running. The RE was measured at speeds of 75%, 85%, and 95% of the lactate threshold at 3.5 mmol·L−1 during the follicular (FP) and luteal phases (LP) of the menstrual cycle. The RE was evaluated as oxygen consumption (mL·kg·min−1 (O2C_min), mL·kg−1·km−1 (O2C_km)) and caloric unit cost (kcal·kg−1·km−1 (EC)) during both phases.
Results: There were no significant differences in body composition or resting physiological measurements between the LP and FP (p > .05). Physiological responses measured during RE tests were similar in both phases (p > .05). The RE measured as O2C_min, O2C_km, and EC was significantly lower during the LP than during the FP (p < .05). The RE defined as O2C_ min significantly increased with speed (p < .05), but RE defined as O2C_km and EC was unaffected by speed increment (p > .05).
Conclusion: The RE is better in the LP than the FP and is independent of running speed when RE is evaluated as O2C_km and EC. The menstrual cycle had no effect on body composition and physiological variables measured at rest.
– Erreka Gil-Rey, Sara Maldonado-Martín, and Esteban M. Gorostiaga
Purpose: The aim of this study was to compare the widely used accelerometer activity cut-points derived from the absolute moderate intensity recommendation (3‒6 METs), with relative intensity cut-points according to maximal cardiorespiratory fitness (46%‒63% V˙O2maxV˙O2max) and to individual lactate thresholds (LT1 and LT2) in postmenopausal women.
Accuracy of Impedance Cardiography for Hemodynamic Assessment During Rest and Exercise in Wheelchair Rugby Players
Method: Thirty postmenopausal women performed several exercise tests with measures of heart rate, blood lactate, accelerometer activity counts and oxygen consumption. Individual regressions were developed to derive the accelerometer activity counts at absolute and relative moderate intensity recommendations and at individual LTs.
Results: The activity counts calculated at the lower moderate intensity boundary were lower for the absolute 3 METs threshold (2026 ± 808 ct·min−1) compared to relative 46 % V˙O2maxV˙O2max intensity threshold (p < .01, ES: 1.95) and LT1 (p < .01, ES: 2.27), which corresponded to 4.6 ± 0.7 METs. The activity counts at the upper moderate intensity boundary were higher for LT2 (7249 ± 2499 ct·min−1) compared to the absolute 6 METs threshold (p < .01, ES: 0.72) and relative 63% V˙O2maxV˙O2max intensity threshold (p < .01, ES: 0.55). The interindividual variability in activity counts at relative intensity thresholds was high (CV = 30–34%), and was largely explained by cardiorespiratory fitness level (R2 = ~ 50%).
Conclusion: Individually tailored (relative to V˙O2maxV˙O2max or submaximal LTs) rather than fixed accelerometer intensity cut-points derived from the classic absolute moderate physical activity intensity (3–6 METs) would result in a more accurate measurement of an individual´s activity levels and reduce the risk of overestimating or underestimating physical activity.
– Łukasz A. Małek, Anna Mróz, Anna Czajkowska, Andrzej Kosmol, Anna Ogonowska-Słodownik, Bartosz Molik, and Natalia Morgulec-Adamowicz
Purpose: The aim of the study was to analyze the accuracy of impedance cardiography (ICG) for hemodynamic assessment in wheelchair rugby players during rest and exercise.
Exploring the Intersection Between Disability and Overweightness in Physical Education Among Females With Visual Impairments
Method: The study included 21 players (mean age 33.0 ± 5.4, 86% male) with posttraumatic tetraplegia. ECG, echocardiography, and gas exchange analysis during rest and exercise were used to obtain heart rate (HR), stroke volume (SV), and cardiac output (CO) for comparison with PhysioFlow®.
Results: There was a good correlation between reference methods and ICG for HR, SV, CO at rest and CO at peak exercise (r = 0.69–0.77, p < .001) and a very good correlation for peak HR (r = 0.91, p < .0001). ICG overestimated SV at rest, CO at rest, and peak CO, which resulted in low intraclass correlation coefficients (ICC = 0.250 and 0.570).
Conclusion: ICG can serve as a good estimate of basic hemodynamic parameters during rest and exercise in wheelchair rugby players but overestimates stroke volume and cardiac output.
– Justin A. Haegele, Xihe Zhu, and Katherine Holland
Purpose: The purpose of this study was to adopt an explicitly intersectional approach to examine the experiences of women identifying as having a visual impairment and as being overweight or obese in integrated physical education (PE).
Relationship Between Resting Heart Rate Variability and Intermittent Endurance Performance in Novice Soccer Players
Method: An interpretative phenomenological analysis (IPA) research approach was used, and six women (ages 25–34) with visual impairments who identified as being overweight or obese acted as participants. The sources of data included semistructured audiotaped telephone interviews and reflective interview notes. Data were analyzed thematically using a three-step analytic process informed by IPA.
Results: Based on the data analysis, three inter-related themes emerged. The first theme, restricted/reluctant participation, described participants’ experiences with PE activity restrictions and the influence of visual impairment and overweight or obesity on these restrictions. The second theme, teacher discrimination, described participants’ recollection of discriminatory practices by physical educators that were influenced by perceptions of inability. Finally, the third theme, isolation, teasing and surveillance issues, described challenging social instances and how those instances were influenced by body size and disability status.
Conclusion: Using an IPA approach, three themes emerged that exposed central experiences that were informed by the participants’ identities as individuals with visual impairments and being overweight or obese. Through the lens of intersectionality, these themes contribute to our understanding of how these identities interacted to contribute to disadvantaging experiences in PE.
– Lucas A. Pereira, César C. Cal Abad, Daniel F. Leiva, Gabriel Oliveira, Everton C. Carmo, Ronaldo Kobal, and Irineu Loturco
Purpose: This study examined the relationships between the Yo-Yo Intermittent Recovery Test level 1 (Yo-Yo IR1) and resting heart rate variability (HRV) and submaximal 5ʹ-5ʹ test derived measures in novice male soccer players.
Validity of Activity Trackers in Estimating Energy Expenditure During High-Intensity Functional Training
Results: The highest correlation score was observed between Yo-Yo IR1 performance and resting HRV, when the absolute age was used as confounder (r = 0.72; p < .05).
Conclusion: We observed that a practical measure of parasympathetic activity at rest is largely associated with performance obtained during a traditional intermittent endurance performance test.
– Cody E. Morris, Paige A. Wessel, Rachel A. Tinius, Mark A. Schafer, and Jill M. Maples
Purpose: The purpose of this study was to evaluate the agreement of five commercially available accelerometers in estimating energy expenditure while performing an acute bout of high-intensity functional training (HIFT).
Strength Loss After Eccentric Exercise Is Related to Oxidative Stress but Not Muscle Damage Biomarkers
Method: Participants (n = 47; average age: 28.5 ± 11.6 years) consisted of recreationally active, healthy adults. Each participant completed a session of HIFT: a 15-minute workout consisting of 12 repetitions each of air-squats, sit-ups, push-ups, lunges, pull-ups, steps-ups, and high-knees; performed circuit-style by completing as many rounds as possible. During this session, each participant wore the Cosmed K4b2 portable metabolic analyzer (PMA) and five different accelerometers (ActiGraph GT3X, Nike Fuelband, Fitbit One, Fitbit Charge HR, and Jawbone UP Move).
Results: Four of the five activity trackers reported lower (p < .05) total EE values compared to the PMA during the acute bout of HIFT. The waist-mounted device (ActiGraph, 182.55 ± 37.93 kcal) was not significantly different from, and most closely estimated caloric expenditure compared to the PMA (144.99 ± 37.13 kcal) (p = .056). A repeated-measures ANOVA showed that all activity trackers were significantly different from the reference measure (PMA) (p < .05). Systematic relative agreement between the activity trackers was calculated, exhibiting a significant ICC = 0.426 (F (46,230) = 5.446 (p < .05)).
Conclusion: The wrist- and hip-mounted activity trackers did not accurately assess energy expenditure during HIFT exercise. With the exception of the ActiGraph GT3X, the remaining four activity trackers showed inaccurate estimates of the amount of kilocalories expended during the HIFT exercise bout compared to the PMA.
– Hayriye Çakir-Atabek, Bircan Dokumaci, and Cihan Aygün
Purpose: The purpose of this study was to investigate (a) time-dependent changes in muscle damage (MD) biomarkers, oxidative stress (OS) indices, and maximum strength performance; (b) the relationship between changes in maximum strength performance and changes in MD and OS indices; and (c) whether eccentric exercise-induced MD is related to OS.
Accelerometer and GPS Data to Analyze Built Environments and Physical Activity
Method: Twenty-nine male volunteers (age: 22.13 ± 3.1 years) participated in the study. Participants performed 60 maximal eccentric actions of the elbow flexors at a constant velocity of 60°·s−1. Maximum isokinetic strength (MIS), visual analog scale soreness scores, serum creatine kinase (CK) activity, total antioxidant status, total oxidant status (TOS), protein carbonyl (PCO), and 8-hydroxydeoxyguanosine level were analyzed. Blood samples were obtained before, immediately after, and 24 h, 48 h, and 96 h after the eccentric exercise. Change in total work (%ΔTWk), peak torque (%ΔPT), and OS index were calculated.
Results: CK, PCO, and TOS significantly increased over time (p < .05). However, no significant main effect was observed for MIS or any other investigated biomarkers (p > .05). MIS was not related to MD or OS indices. However, %ΔTWk demonstrated a moderate inverse correlation with OS indices. No significant relationship was observed between %ΔPT and any of the selected biomarkers.
Conclusion: Our findings confirm the hypothesis that acute eccentric exercise increases MD biomarkers and OS indices. However, indices of OS damage were significantly related, particularly, to the strength loss of flexors. This finding suggests that the decline in strength performance is not the primary determinant of the magnitude of MD following voluntary eccentric contraction.
– Kosuke Tamura, Jeffrey S. Wilson, Keith Goldfeld, Robin C. Puett, David B. Klenosky, William A. Harper, and Philip J. Troped
Purpose: Most built environment studies have quantified characteristics of the areas around participants’ homes. However, the environmental exposures for physical activity (PA) are spatially dynamic rather than static. Thus, merged accelerometer and global positioning system (GPS) data were utilized to estimate associations between the built environment and PA among adults.
How Does the Adjustment of Training Task Difficulty Level Influence Tactical Behavior in Soccer?
Method: Participants (N = 142) were recruited on trails in Massachusetts and wore an accelerometer and GPS unit for 1–4 days. Two binary outcomes were created: moderate-to-vigorous PA (MVPA vs. light PA-to-sedentary); and light-to-vigorous PA (LVPA vs. sedentary). Five built environment variables were created within 50-meter buffers around GPS points: population density, street density, land use mix (LUM), greenness, and walkability index. Generalized linear mixed models were fit to examine associations between environmental variables and both outcomes, adjusting for demographic covariates.
Results: Overall, in the fully adjusted models, greenness was positively associated with MVPA and LVPA (odds ratios (ORs) = 1.15, 95% confidence interval (CI) = 1.03, 1.30 and 1.25, 95% CI = 1.12, 1.41, respectively). In contrast, street density and LUM were negatively associated with MVPA (ORs = 0.69, 95% CI = 0.67, 0.71 and 0.87, 95% CI = 0.78, 0.97, respectively) and LVPA (ORs = 0.79, 95% CI = 0.77, 0.81 and 0.81, 95% CI = 0.74, 0.90, respectively). Negative associations of population density and walkability with both outcomes reached statistical significance, yet the effect sizes were small.
Conclusion: Concurrent monitoring of activity with accelerometers and GPS units allowed us to investigate relationships between objectively measured built environment around GPS points and minute-by-minute PA. Negative relationships between street density and LUM and PA contrast evidence from most built environment studies in adults. However, direct comparisons should be made with caution since most previous studies have focused on spatially fixed buffers around home locations, rather than the precise locations where PA occurs.
– João Cláudio Machado, Daniel Barreira, Israel Teoldo, Bruno Travassos, João Bosco Júnior, João Otacílio Libardoni Dos Santos, and Alcides José Scaglia
Purpose: This study aimed to investigate if player tactical skill level and age category influence team performance and player exploratory behavior in tasks with different difficulty levels.
Age-Based Prediction of Maximal Heart Rate in Children and Adolescents: A Systematic Review and Meta-Analysis
Method: In total, 48 youth male soccer players participated in the study (U15, n = 24, mean age = 13.06 ± 1.53 years; U17, n = 24, mean age = 16.89 ± 0.11 years). Player tactical skills were evaluated through the System of Tactical Assessment in Soccer (FUT-SAT), allowing them to be organized into three groups according to tactical efficiency: Higher tactical skill level (Group 01), Intermediate tactical skill level (Group 02), and Lower tactical skill level (Group 03). Next, Group 01 and Group 03 of both categories performed six Small-Sided and Conditioned Games (SSCG) each, namely three High difficulty SSCGs and three Low difficulty SSCGs. Team performance and players’ exploratory behavior were analyzed through the Offensive Sequences Characterization System and Lag Sequential Analysis, respectively.
Results: We found that team performance and players’ exploratory behavior were influenced both by the age and tactical skill level of the players, as well as by task difficulty level.
Conclusion: Therefore, in an attempt to improve player performance, practitioners must carefully manipulate key task constraints to adapt training task difficulty levels to player age and tactical skill level.
– Zackary S. Cicone, Clifton J. Holmes, Michael V. Fedewa, Hayley V. MacDonald, and Michael R. Esco
Purpose: Maximal heart rate (MHR) is an important physiologic tool for prescribing and monitoring exercise in both clinical and athletic settings. However, prediction equations developed in adults may have limited accuracy in youth. The purpose of this study was to systematically review and analyze the available evidence regarding the validity of commonly used age-based MHR prediction equations among children and adolescents.
Method: Included articles were peer-reviewed, published in English, and compared measured to predicted MHR in male and female participants <18 years old. The standardized mean difference effect size (ES) was used to quantify the accuracy of age-predicted MHR values and a priori moderators were examined to identify potential sources of variability.
Results: The cumulative results of 20 effects obtained from seven articles revealed that prediction equations did not accurately estimate MHR (ES= 0.44, p < .05) by 6.3 bpm (bpm). Subgroup analyses indicated that the Fox equation (MHR = 220–age) overestimated MHR by 12.4 bpm (ES = 0.95, p < .05), whereas the Tanaka equation (MHR = 208–0.7*age) underestimated MHR by 2.7 bpm (ES = −0.34, p < .05).
Conclusion: Age-based MHR equations derived from adult populations are not applicable to children. However, if the use of age-based equations cannot be avoided, we recommend using the Tanaka equation, keeping in mind the range of error reported in this study. Future research should control for potential pubertal influences on sympathetic modulation during exercise to facilitate the development of more age-appropriate methods for prescribing exercise intensity.