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Anthropometrics and Body Composition in East African Runners: Potential Impact on Performance

Martin Mooses and Anthony C. Hackney

Maximal oxygen uptake (V̇O2max), fractional utilization of V̇O2max during running, and running economy (RE) are crucial factors for running success for all endurance athletes. Although evidence is limited, investigations of these key factors indicate that East Africans’ superiority in distance running is largely due to a unique combination of these factors. East African runners appear to have a very high level of RE most likely associated, at least partly, with anthropometric characteristics rather than with any specific metabolic property of the working muscle. That is, evidence suggest that anthropometrics and body composition might have important parameters as determinants of superior performance of East African distance runners. Regrettably, this role is often overlooked and mentioned as a descriptive parameter rather than an explanatory parameter in many research studies. This brief review article provides an overview of the evidence to support the critical role anthropometrics and body composition has on the distance running success of East African athletes. The structural form and shape of these athletes also has a downside, because having very low BMI or body fat increases the risk for relative energy deficiency in sport (RED-S) conditions in both male and female runners, which can have serious health consequences.

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The Cortisol Awakening Response: Association With Training Load in Endurance Runners

Travis Anderson, Amy R. Lane, and Anthony C. Hackney

The cortisol awakening response (CAR) is commonly used as a marker of psychological stress; however, it is unknown whether CAR is affected by regular physical-exercise-induced stress. Purpose: To assess the relationship between training load and CAR. Methods: Recreational endurance athletes were recruited from local running clubs. Subjects (n = 15) completed training logs for 2 wk, with various training loads, including psychometric analysis (Recovery-Stress Questionnaire for Athletes). Subjects provided saliva samples each day immediately after waking and 30 min postwaking. Samples were analyzed for cortisol concentration via enzyme-linked immunosorbent assay and subsequently were analyzed for CAR and CAR%. Daily training load was calculated and analyzed as training impulse. Simple linear regression was used to assess the relationship between CAR and training impulse. Results: CAR (r 2 = .352, P = .025) and CAR% (r 2 = .373, P = .012) both showed a significant negative relationship with training load. Conclusions: These results suggest that CAR is affected by regular exercise training loads in recreational athletes. It is recommended that future CAR research control for fitness level and exercise training load in physically active populations.

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Substrate Responses to Submaximal Exercise in the Midfollicular and Midluteal Phases of the Menstrual Cycle

Anthony C. Hackney, Mary Ann McCracken-Compton, and Barbara Ainsworth

This study examined substrate metabolism responses of eumenorrheic women to different intensities of submaximai exercise at the midfollicular (MF) and the midluteal (ML) phases of the menstrual cycle. Nine women performed a 30-min treadmill run in which the exercise intensity was made more difficult every 10 min (35%, 60%, and 75%). Carbohydrate (CHO) utilization and oxidation rates for the 35% and 60% intensities during the ML session were significantly lower than during the comparable intensities in the MF. Conversely, lipid utilization and oxidation were significantly greater during the 35% and 60% ML session than in the MF session. At 75%, however, the ML and MF CHO-lipid utilization and oxidation rates were not significantly different from one another. Thus, the phase of the menstrual cycle in eumenorrheic women does influence metabolic substrate usage during low- to moderate-intensity submaximai exercise, probably due to changes in the endogenous levels of the female sex hormones.

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Rest Interval Between Resistance Exercise Sets: Length Affects Volume But Not Creatine Kinase Activity or Muscle Soreness

Renato Evangelista, Rafael Pereira, Anthony C. Hackney, and Marco Machado

Purpose:

To compare differences between two different rest interval lengths between sets on the volume completed, muscle damage and muscle soreness during a resistance exercise bout.

Methods:

Twenty-eight healthy sedentary men (18 ± 1 y old) volunteered to participate in this study and were divided into the 1 min (1RI; n = 14) or 3 min (3RI; n = 14) rest interval length between sets. They were submitted to maximal voluntary isometric contraction strength (MVC) and then performed a resistance exercise protocol constituted for three sets of biceps curl at 40% of MVC with 1 min (1RI group) or 3 min (3RI group) interval length between sets. Each bout was performed to voluntary fatigue and the workout volume completed was calculated. Subjects provided blood samples before each bout, and at 24, and 48 h following exercise to evaluate serum CK activity. Muscle soreness was analyzed through visual analog scale, which was presented to subjects before frst bout, immediately after exercise protocol and at 24, and 48 h following exercise.

Results:

The results demonstrated that the subjects with longer rest intervals provide greater workout volume as expected, but there were no differences in serum CK activity and muscle soreness between groups.

Conclusion:

Training with highvolume, low-intensity resistance training, exercising with short rest intervals does not appear to present any additional challenge to recovery in untrained subjects.

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Female Physiology–Endocrinology: Education Is Lacking and Innovation Is Needed!

Anthony C. Hackney and Kirsty J. Elliott-Sale

Throughout their lifespans, women undergo unique endocrinological changes relative to their reproductive hormones. The influence of how the female sex steroid hormones have nonreproductive actions is a trending topic of great interest in the exercise–sports sciences, especially among women of reproductive age. Herein, we present several key points on our perspective for moving the study of this topic forward in the future. These are (a) encouraging researchers to pursue high-quality research on female physiology–endocrinology in the exercise–sports science setting, (b) the need for exercise–sports science educational curriculums at the university level to embrace the study of female physiology–endocrinology area, and (c) the need for innovation in the study of this topic. As such, we propose using research design models involving supraphysiological hormonal states in vivo, that is, pregnancy and in vitro fertilization treatment, to gain new insights on sex steroid hormonal actions in women. Herein, we provide the rationale for our recommendations as well as a brief physiological overview of these clinical states. We acknowledge, exercise sports sciences need more studies on women! But there is a need to “think outside the box” on this topic, and we encourage researchers to be unconventional, be bold, think creatively, and contemplate whether these supraphysiological hormonal states might give them insightful information on female physiology and ovarian sex steroid hormones actions.

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Impact of Premenstrual Syndrome Symptoms on Sport Routines in Nonelite Athlete Participants of Summer Olympic Sports

Raul C.R. Prado, Hannah N. Willett, Monica Y. Takito, and Anthony C. Hackney

Purpose: Most women during their lifetime experience a combination of premenstrual syndrome (PMS) symptoms (eg, menstrual cramps) before and often to the end of menstruation. However, the impact of these symptoms on sport routines (eg, performance, training absence) during phases around menstruation is still unclear. Therefore, we investigated the impact of PMS symptoms on sport routines among nonelite athletes over 3 phases related to menstruation. Methods: An online questionnaire was developed to recruit nonelite female athletes who participate in summer Olympic sports. Participants were allocated into 2 groups: those who experienced mild to moderate PMS symptoms (no-PMS) and those with severe PMS symptoms (p-PMS). Two hundred thirty-four responses from eumenorrheic women (p-PMS = 78%) were considered valid. An unpaired Student t test was conducted to compare demographic characteristics between groups and chi-square test to evaluate the impact of PMS status on sport routines between groups. Results: A significant (P < .05) proportion of women in the p-PMS group changed their training schedule because of menstrual (55%) and premenstrual (61%) symptoms compared with the no-PMS group. Overall, all participants indicated that training (P = .01) and competitive (P < .01) performance are impacted during menstruation, followed by a greater impact (P < .05) in the p-PMS group before menstruation. Conclusion: The presence of PMS symptoms reduces training and competitive performance, primarily during and before menstruation, respectively. Severity of PMS symptoms was significantly associated with alterations in training schedule but not with competitive schedule.

Open access

Dietary Supplements for Athletic Performance in Women: Beta-Alanine, Caffeine, and Nitrate

Molly J. Murphy, Blake R. Rushing, Susan J. Sumner, and Anthony C. Hackney

Beta-alanine, caffeine, and nitrate are dietary supplements generally recognized by the sport and exercise science community as evidence-based ergogenic performance aids. Evidence supporting the efficacy of these supplements, however, is greatly skewed due to research being conducted primarily in men. The physiological differences between men and women, most notably in sex hormones and menstrual cycle fluctuations, make generalizing male data to the female athlete inappropriate, and potentially harmful to women. This narrative review outlines the studies conducted in women regarding the efficacy of beta-alanine, caffeine, and nitrate supplementation for performance enhancement. Only nine studies on beta-alanine, 15 on caffeine, and 10 on nitrate in healthy women under the age of 40 years conducted in normoxia conditions were identified as relevant to this research question. Evidence suggests that beta-alanine may lower the rate of perceived exertion and extend training bouts in women, leading to greater functional adaptations. Studies of caffeine in women suggest the physiological responder status and caffeine habituation may contribute to caffeine’s efficacy, with a potential plateau in the dose–response relationship of performance enhancement. Nitrate appears to vary in influence based on activity type and primary muscle group examined. However, the results summarized in the limited literature for each of these three supplements provide no consensus on dosage, timing, or efficacy for women. Furthermore, the literature lacks considerations for hormonal status and its role in metabolism. This gap in sex-based knowledge necessitates further research on these ergogenic supplements in women with greater considerations for the effects of hormonal status.

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The Relationship Between Serum and Salivary Cortisol Levels in Response to Different Intensities of Exercise

Mitch D. VanBruggen, Anthony C. Hackney, Robert G. McMurray, and Kristin S. Ondrak

Purpose:

The effect of exercise intensity on the tracking of serum and salivary cortisol responses was examined in 12 endurance-trained males (maximal oxygen uptake [VO2max] = 58.2 ± 6.4 mL/kg/min).

Methods:

Subjects rested for 30 min (control) and exercised on a cycle ergometer for 30 min at 40% (low), 60% (moderate), and 80% (high intensity) of VO2max on separate days. Serum and saliva samples were collected pretrial, immediately posttrial, and 30 min into the recovery period from each trial.

Results:

Cortisol responses increased significantly for both serum (40.4%; P = .001) and saliva (170.6%; P = .007) only in response to high-intensity exercise. Peak saliva cortisol occurred at 30 min of recovery, whereas peak serum was at the immediate posttrial sampling time point. The association between serum and saliva cortisol across all trials was examined using concordance correlation (R c) analysis, which accounts for repeated measures. The overall correlation between serum and saliva cortisol levels in all matched samples was significant (R c = 0.728; P = .001). The scatter plot revealed that salivary cortisol responses tracked closely to those of serum at lower concentrations, but not as well at higher concentrations.

Conclusions:

Findings suggest salivary measurements of cortisol closely mirror those in the serum and that peak salivary concentrations do not occur until at least 30 min into the recovery from intense exercise.

Open access

Sport-Science Research on Female Athletes: Dealing With the Paradox of Concurrent Increases in Quantity and Quality

Dionne A. Noordhof, Xanne A.K. Janse de Jonge, Anthony C. Hackney, Jos J. de Koning, and Øyvind Sandbakk

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L-Arginine Improves Endurance to High-Intensity Interval Exercises in Overweight Men

Ali Daraei, Sajad Ahmadizad, Hiwa Rahmani, Anthony C. Hackney, Kelly E. Johnson, Ismail Laher, Ayoub Saeidi, and Hassane Zouhal

The effects of acute consumption of L-Arginine (L-Arg) in healthy young individuals are not clearly defined, and no studies on the effects of L-Arg in individuals with abnormal body mass index undertaking strenuous exercise exist. Thus, we examined whether supplementation with L-Arg diminishes cardiopulmonary exercise testing responses, such as ventilation (VE), VE/VCO2, oxygen uptake (VO2), and heart rate, in response to an acute session of high-intensity interval exercise (HIIE) in overweight men. A double-blind, randomized crossover design was used to study 30 overweight men (age, 26.5 ± 2.2 years; body weight, 88.2 ± 5.3 kilogram; body mass index, 28.0 ± 1.4 kg/m2). Participants first completed a ramped-treadmill exercise protocol to determine VO2max velocity (vVO2max), after which they participated in two sessions of HIIE. Participants were randomly assigned to receive either 6 g of L-Arg or placebo supplements. The HIIE treadmill running protocol consisted of 12 trials, including exercise at 100% of vVO2max for 1 min interspersed with recovery intervals of 40% of vVO2max for 2 min. Measurements of VO2 (ml·kg−1·min−1), VE (L/min), heart rate (beat per min), and VE/VCO2 were obtained. Supplementation with L-Arg significantly decreased all cardiorespiratory responses during HIIE (placebo+HIIE vs. L-Arg+HIIE for each measurement: VE [80.9 ± 4.3 L/min vs. 74.6 ± 3.5 L/min, p < .05, ES = 1.61], VE/VCO2 [26.4 ± 1.3 vs. 24.4 ± 1.0, p < .05, ES = 1.8], VO2 [26.4 ± 0.8 ml·kg−1·min−1 vs. 24.4 ± 0.9 ml·kg−1·min−1, p < .05, ES = 2.2], and heart rate [159.7 ± 6.3 beats/min vs. 155.0 ± 3.7 beats/min, p < .05, d = 0.89]). The authors conclude consuming L-Arg before HIIE can alleviate the excessive physiological strain resulting from HIIE and help to increase exercise tolerance in participants with a higher body mass index who may need to exercise on a regular basis for extended periods to improve their health.