Factors Influencing the Hepcidin Response to Exercise: An Individual Participant Data Meta-analysis.

Background: Hepcidin, the master iron regulatory hormone, has been shown to peak 3-6 h postexercise, and is likely a major contributor to the prevalence of iron deficiency in athletes. Although multiple studies have investigated the hepcidin response to exercise, small sample sizes preclude the generalizability of current research findings.

Objective: The aim of this individual participant data meta-analysis was to identify key factors influencing the hepcidin-exercise response.

Peak match acceleration demands differentiate between elite youth and professional football players.

Youth footballers need to be developed to meet the technical, tactical, and physical demands of professional level competition, ensuring that the transition between competition levels is successful. To quantify the physical demands, peak match intensities have been measured across football competition tiers, with team formations and tactical approaches shown to influence these physical demands. To date, no research has directly compared the physical demands of elite youth and professional footballers from a single club utilising common formations and tactical approaches.

Positional and temporal differences in peak match running demands of elite football.

Temporal changes in the total running demands of professional football competition have been well documented, with absolute running demands decreasing in the second half. However, it is unclear whether the peak match running demands demonstrate a similar decline. A total of 508 GPS files were collected from 44 players, across 68 matches of the Australian A-League.

Between-match variation of peak match running intensities in elite football.

Peak match running intensities have recently been introduced to quantify the peak running demands of football competition, across incremental time intervals, to inform training practices. However, their between-match variation is yet to be comprehensively reported, limiting the ability to determine meaningful changes in peak match running intensities. The current study aimed to quantify the between-match variability in peak match running intensities across discrete moving average durations (1-10 min).

Temporal distribution of peak running demands relative to match minutes in elite football.

The peak match running demands of football (soccer) have been quantified across time durations of 1-10 min, however, little is known as to when the peak match running demands occur within match play. Data were collected from 44 elite footballers, across 68 fixtures (Files = 413, mean ± SD; 11 ± 8 observations per player, range; 1-33), with peak match running demands quantified for each playing half at ten incremental rolling average durations (1 min rolling averages, 2 min rolling averages, etc.).

A contemporary understanding of iron metabolism in active premenopausal females.

Iron metabolism research in the past decade has identified menstrual blood loss as a key contributor to the prevalence of iron deficiency in premenopausal females. The reproductive hormones estrogen and progesterone influence iron regulation and contribute to variations in iron parameters throughout the menstrual cycle. Despite the high prevalence of iron deficiency in premenopausal females, scant research has investigated female-specific causes and treatments for iron deficiency.

An Analysis of Warm-Up Strategies at a Cross-Country Skiing National Championship.

Purpose: To provide a descriptive analysis of the warm-up (WU) strategies employed by cross-country skiers prior to distance and sprint competitions at a national championship and to compare the skiers' planned and executed WUs prior to the respective competitions.

Methods: Twenty-one national- and international-level skiers (11 women and 10 men) submitted WU plans prior to the distance and sprint competitions, and after the competitions, reported any deviations from the plans. Skiers used personal monitors to record heart rate (HR) during WU, races, and cooldown.

Hormonal Contraceptive Use in Football Codes in Australia.

The recent launch of the new National elite women's football competitions in Australia has seen a 20-50% increase in grassroots female participation. With the growing participation across grassroots to elite competitions, understanding the health of female athletes should be prioritized. In elite level athletes, hormonal contraceptive (HC) use is common (~50%), however, little is known about the prevalence and reasons for use and disuse of HC in elite female football athletes.

Not as simple as it seems: Front foot contact kinetics, muscle function and ball release speed in cricket pace bowlers.

This study investigated the relationship between front foot contact (FFC) ground reaction forces (GRF) during the delivery stride, lower-limb strength, eccentric dexterity and power, and ball release speed (BRS) among pace bowlers. Thirteen high-level male pace bowlers performed double and single leg drop landings; isometric mid-thigh pull; countermovement jump; and pace bowling (two-over bowling spell measuring BRS and FFC GRF). The relationship between assessed variables and BRS was determined via frequentist and Bayesian multiple linear regression.

Multidisciplinary rehabilitation reduces hypothalamic grey matter volume loss in individuals with preclinical Huntington's disease: A nine-month pilot study.

Background: Hypothalamic pathology is a well-documented feature of Huntington's disease (HD) and is believed to contribute to circadian rhythm and habitual sleep disturbances. Currently, no therapies exist to combat hypothalamic changes, nor circadian rhythm and habitual sleep disturbances in HD.

Objective: To evaluate the effects of multidisciplinary rehabilitation on hypothalamic volume, brain-derived neurotrophic factor (BDNF), circadian rhythm and habitual sleep in individuals with preclinical HD.

Influence of Immune and Nutritional Biomarkers on Illness Risk During Interval Training.

Unlabelled: Intensive training periods may negatively influence immune function, but the immunological consequences of specific high-intensity-training (HIT) prescriptions are not well defined.

Purpose: To explore whether 3 different HIT prescriptions influence multiple health-related biomarkers and whether biomarker responses to HIT were associated with upper-respiratory-illness (URI) risk.

Methods: Twenty-five male cyclists and triathletes were randomized to 3 HIT groups and completed 12 HIT sessions over 4 wk.

Characterizing the plasma metabolome during 14 days of live-high, train-low simulated altitude: A metabolomic approach.

New Findings: What is the central question of this study? Does 14 days of live-high, train-low simulated altitude alter an individual's metabolomic/metabolic profile? What is the main finding and its importance? This study demonstrated that ∼200 h of moderate simulated altitude exposure resulted in greater variance in measured metabolites between subject than within subject, which indicates individual variability during the adaptive phase to altitude exposure. In addition, metabolomics results indicate that altitude alters multiple metabolic pathways, and the time course of these pathways is different over 14 days of altitude exposure. These findings support previous literature and provide new information on the acute adaptation response to altitude.

Commercially available compression garments or electrical stimulation do not enhance recovery following a sprint competition in elite cross-country skiers.

This study investigated whether commercially available compression garments (COMP) exerting a moderate level of pressure and/or neuromuscular electrical stimulation (NMES) accelerate recovery following a cross-country sprint skiing competition compared with a control group (CON) consisting of active recovery only. Twenty-one senior (12 males, 9 females) and 11 junior (6 males, 5 females) Swedish national team skiers performed an outdoor sprint skiing competition involving four sprints lasting ∼3-4 min. Before the competition, skiers were matched by sex and skiing level (senior versus junior) and randomly assigned to COMP (n = 11), NMES (n = 11) or CON (n = 10).

Intravenous Iron Does Not Augment the Hemoglobin Mass Response to Simulated Hypoxia.

Purpose: Iron is integral for erythropoietic adaptation to hypoxia, yet the importance of supplementary iron compared with existing stores is poorly understood. The aim of the present study was to compare the magnitude of the hemoglobin mass (Hbmass) in response to altitude in athletes with intravenous (IV), oral, or placebo iron supplementation.

Methods: Thirty-four, nonanemic, endurance-trained athletes completed 3 wk of simulated altitude (3000 m, 14 h·d), receiving two to three bolus iron injections (ferric carboxymaltose), daily oral iron supplementation (ferrous sulfate), or a placebo, commencing 2 wk before and throughout altitude exposure.

Influence of combined iron supplementation and simulated hypoxia on the haematological module of the athlete biological passport.

The integrity of the athlete biological passport (ABP) is underpinned by understanding normal fluctuations of its biomarkers to environmental or medical conditions, for example, altitude training or iron deficiency. The combined impact of altitude and iron supplementation on the ABP was evaluated in endurance-trained athletes (n = 34) undertaking 3 weeks of simulated live-high: train-low (14 h.d , 3000 m).

Relationship Between Pretraining Subjective Wellness Measures, Player Load, and Rating-of-Perceived-Exertion Training Load in American College Football.

Context: The relationship between pretraining subjective wellness and external and internal training load in American college football is unclear.

Purpose: To examine the relationship of pretraining subjective wellness (sleep quality, muscle soreness, energy, wellness Z score) with player load and session rating of perceived exertion (s-RPE-TL) in American college football players.

Methods: Subjective wellness (measured using 5-point, Likert-scale questionnaires), external load (derived from GPS and accelerometry), and s-RPE-TL were collected during 3 typical training sessions per week for the second half of an American college football season (8 wk).

Within-Season Distribution of External Training and Racing Workload in Professional Male Road Cyclists.

Purpose: To describe the within-season external workloads of professional male road cyclists for optimal training prescription.

Methods: Training and racing of 4 international competitive professional male cyclists (age 24 ± 2 y, body mass 77.6 ± 1.

The 30-15 Intermittent Fitness Test: Can It Predict Outcomes in Field Tests of Anaerobic Performance?

This study determined whether a composite assessment of intermittent fitness could be used to quantify performance in several anaerobic tasks. Fifty-two male recreational athletes (age: 24.3 ± 4.

Pre-Altitude Serum Ferritin Levels and Daily Oral Iron Supplement Dose Mediate Iron Parameter and Hemoglobin Mass Responses to Altitude Exposure.

Purpose: To investigate the influence of daily oral iron supplementation on changes in hemoglobin mass (Hbmass) and iron parameters after 2-4 weeks of moderate altitude exposure.

Methods: Hematological data collected from 178 athletes (98 males, 80 females) exposed to moderate altitude (1,350-3,000 m) were analysed using linear regression to determine how altitude exposure combined with oral iron supplementation influenced Hbmass, total iron incorporation (TII) and blood iron parameters [ferritin and transferrin saturation (TSAT)].

Results: Altitude exposure (mean ± s: 21 ± 3 days) increased Hbmass by 1.

Acute hypoxic exercise does not alter post-exercise iron metabolism in moderately trained endurance athletes.

Purpose: This study measured the influence of acute hypoxic exercise on Interleukin-6 (IL-6), hepcidin, and iron biomarkers in athletes.

Methods: In a repeated measures design, 13 moderately trained endurance athletes performed 5 × 4 min intervals at 90 % of their peak oxygen consumption velocity (vVO2peak) in both normoxic [NORM, fraction of inspired oxygen (F IO2) = 0.2093, 15.

Iron status and the acute post-exercise hepcidin response in athletes.

This study explored the relationship between serum ferritin and hepcidin in athletes. Baseline serum ferritin levels of 54 athletes from the control trial of five investigations conducted in our laboratory were considered; athletes were grouped according to values <30 μg/L (SF<30), 30-50 μg/L (SF30-50), 50-100 μg/L (SF50-100), or >100 μg/L (SF>100). Data pooling resulted in each athlete completing one of five running sessions: (1) 8 × 3 min at 85% vVO2peak; (2) 5 × 4 min at 90% vVO2peak; (3) 90 min continuous at 75% vVO2peak; (4) 40 min continuous at 75% vVO2peak; (5) 40 min continuous at 65% vVO2peak.