The Prevalence of Stress Fractures and the Associated LEAF-Q Responses, Self-Reported Exercise Volume and Dietary Behaviors in Female Recreational Runners.

Previous research suggests a high prevalence of low energy availability (LEA) and stress fractures (SF) among competitive female endurance athletes. However, much less is known about these issues among recreational female runners. This study aimed to assess the prevalence and number of self-reported SF and risk of LEA among noncompetitive, recreationally active female runners, aged 18 - 25 years. Additionally, it compared characteristics between females with a history of multiple SF vs. one or no SF, and between those 'at risk' vs. 'not at risk' of LEA. Female recreational runners (n=485) completed an online survey that included the Low Energy Availability in Females Questionnaire (LEAF-Q) and the Disordered Eating Screening Assessment (DESA-6). Thirty-three percent of participants reported ≥ 2 SF. Eighty-two percent of the ≥ 2 SF group were classified as 'at risk' of LEA (LEAF-Q score ≥ 8). In addition, ≥ 2 SF was associated with higher total LEAF-Q score, self-reported intentional food restriction for weight loss, and self-reported current eating disorder while weekly exercise duration was inversely associated with ≥ 2 SF. In conclusion, one-third of participants had multiple SF with a majority (82%) of this group classified as 'at risk' of LEA. Screening tools such as the LEAF-Q and DESA-6 are useful tools to identify characteristics associated with multiple SF in this demographic, especially questions regarding food restriction and the presence of a current or previous eating disorder.

Risk of Low Energy Availability, Disordered Eating, and Menstrual Dysfunction in Female Collegiate Runners.

CONTEXT: Collegiate female distance runners may be at risk for low energy availability (LEA) due to increased exercise energy expenditure with or without decreased energy intake. Furthermore, this population has increased risk of disordered eating (DE), which can lead to LEA and negative health consequences, such as menstrual dysfunction (MD). OBJECTIVE: 1) investigate risk of LEA and DE, 2) compare DE, training volume, and weight dissatisfaction among female collegiate runners at risk vs not at risk for LEA, and 3) compare risk for LEA between NCAA (National Collegiate Athletics Association) Division I, II, and III female collegiate runners. DESIGN: Cross-sectional study. SETTING: Free-living. PATIENTS OR OTHER PARTICIPANTS: Female runners (n = 287) who competed on an NCAA (National Collegiate Athletics Association) Division I, II, or III cross-country and/or track team. MAIN OUTCOME MEASURE(S): A 45 question questionnaire was completed which included the Low Energy Availability in Females Questionnaire (LEAF-Q) and the Disordered Eating Screening Assessment (DESA-6). RESULTS: 54.5% (n = 156) of runners were at risk for LEA (score ≥ 8 on LEAF-Q), and 40.8% (n = 117) were at risk for DE (DESA-6 score ≥ 3), and 56.5% (n = 162) reported MD (LEAF-Q subsection MD score ≥ 4). Athletes "at risk" for LEA had significantly higher DESA-6 scores than athletes "not at risk" for LEA (p < 0.001). Athletes "at risk" for LEA had significantly greater weight dissatisfaction than those not at risk for LEA (X23, 156 = 15.92, p = 0.001). Higher weekly training volumes was not associated with risk for LEA (X22, 156 = 4.20, p = 0.112). CONCLUSIONS: A substantial percentage of collegiate female runners were found to be at risk for LEA, DE, and report MD. These findings demonstrate that risk for DE, MD, and weight dissatisfaction are associated with risk for LEA.

Montmorency Cherry Juice Consumption does not Improve Muscle Soreness or Inhibit Pro-inflammatory Monocyte Responses Following an Acute Bout of Whole-body Resistance Training.

Montmorency Cherry Juice (MCJ) may improve acute exercise recovery by attenuating inflammation and oxidative stress. However, the anti-inflammatory effects of MCJ on monocyte responses following resistance exercise have not been explored. Seven resistance-trained males (age: 22.9 ± 4.1 yrs; height: 1.8 ± 0.1 m; weight: 81.7 ± 13.2 kg) participated in this study. Participants completed a placebo-controlled crossover design, drinking either MCJ or placebo beverages, 7 days prior to completing an acute bout of unilateral resistance exercise. Statistical significance was assessed using a withinsubjects repeated measures ANOVA; alpha level p ≤ 0.05. Main effects for time were observed for changes in classical and intermediate monocytes (p ≤ 0.05), but no significant treatment effects were observed for monocyte subtypes p > 0.05. Classical monocytes (CD14+ CD16-) increased and peaked 24 hr post-exercise (placebo 1.14 ± 0.04 and MCJ 1.06 ± 0.06-fold). Intermediate monocytes peaked 48 hr post-exercise increasing 1.82 ± 0.41 and 2.01 ± 0.80- fold. Nonclassical monocytes peaked post-exercise (placebo 1.17 ± 0.31 and MCJ 1.02 ± 0.20-fold). Peak pain visual analog scale (VAS) occurred post-exercise for MCJ (3.63 ± 2.01-fold) and 72 hr post-exercise for placebo (4.26 ± 3.46- fold). IL-6 and pressure pain threshold (PPT) peaked 24 hr post-exercise (IL-6 placebo 3.83 ± 1.01- and MCJ 6.43 ± 3.43-fold) and (PPT placebo 86.37 ± 3.95% and MCJ 82.81 ± 2.90% of pressure needed at pre-exercise). Our data suggests MCJ consumption does not decrease muscle soreness, IL-6, or monocyte subset responses following a high-intensity resistance exercise protocol in resistance-trained males.

No significant effect of caffeine on five kilometer running performance after muscle damage.

Caffeine has documented hypoalgesic effects during exercise. However, there is a lack of research focusing on caffeine's potential analgesic effects to ameliorate delayed onset muscle soreness. A placebo controlled randomized cross-over trial was carried out to determine if 5 mg/kg of body weight (mg/kgBW) of caffeine attenuates muscle pain and improves 5 k running performance following delayed onset muscle soreness. Prior to participating, eleven runners (9 male; 2 female; age, 24.5 ± 6.3 years; height, 173.6 ± 7.8 cm; body mass, 66.3 ± 7.5 kg; BMI, 23.18 kg/m2 ± 1.6; VO2max 61.0 ± 6.1 ml/kg/min-1), were asked to discontinue supplement use for 72 hours and abstain from caffeine consumption for 48 hours. Participants performed a 30-minute downhill run on a treadmill set at -10% grade at 70% VO2max to induce delayed onset of muscle soreness. Participants then returned 48 hours after to complete a 5 k time trial run where they consumed either 5 mg/kgBW of caffeine or a placebo. Rate of perceived exertion and heart rate were taken every two minutes during the trial. There was no detectable statistical difference between 5 k performance between caffeine (1074.9 ± 119.7 sec) or placebo (1053.8 ± 86.8 sec) (p = .41). Algometer readings were similar between both treatments for muscle soreness in the rectus femoris (p = .791) and the vastus medialis oblique (p = .371). Muscle soreness ratings were found to be greater in the caffeine condition compared to the placebo condition (p = .030). There was no effect of treatment on rating of perceived exertion between conditions (p = .574). The present study suggests that caffeine is not effective at reducing muscle soreness, rating of perceived exertion, or improving running performance in a time trial in the presence of muscle soreness.

Effects of Pre-Exercise Ice Slurry Ingestion on Physiological and Perceptual Measures in Athletes with Spinal Cord Injuries.

Athletes with cervical level spinal cord injuries (SCI) have an impaired ability to thermoregulate during exercise, leading to an increased core temperature (Tcore) due to a decrease in sweat response. Elevated Tcore may result in premature onset of fatigue and decreased athletic performance. Therefore, precooling techniques that decrease Tcore before exercise may increase the storage capacity for metabolic heat production, thereby delaying the time before reaching a critically high Tcore. The purpose of this study was to investigate the effects of pre-exercise ice slurry ingestion as a precooling method in elite athletes with SCI during a wheelchair rugby match simulation. Employing a field-based, counterbalanced-design, participants were administered 6.8 g/kg of room temperature (PLB) or ice slurry (IS) beverage during a 20-minute precooling period, before engaging in a 50 and 60 minute on-court training session on day 1 and 2, respectively. Physiological measures, including Tcore and heart rate, and perceptual measures including gastrointestinal and thermal comfort, and rating of perceived exertion, were monitored throughout precooling (minutes 10, 20) and exercise (minutes 10-60). IS had a large effect on Tcore at the midpoint of exercise on day 1 (minute 30) (ES=0.73) and 2 (minute 40) (ES=1.17). Independent samples T-tests revealed significant differences in the perception of thermal comfort between IS and PLB at the midpoint of exercise on day 1 (minute 30) (p=0.04), but not day 2 (minute 40) (p=0.05), indicating that IS may help participants to feel cooler during exercise. Although further research is warranted, pre-exercise ice slurry ingestion may provide an effective means for delaying an increase in Tcore in some athletes with SCI during a wheelchair rugby match.

Risk of Low Energy Availability in National and International Level Paralympic Athletes: An Exploratory Investigation.

(1) Background: The purpose of this study was to examine the symptoms of low energy availability (LEA) and risk of relative energy deficiency in sport (RED-S) symptoms in para-athletes using a multi-parameter approach. (2) Methods: National level para-athletes (n = 9 males, n = 9 females) completed 7-day food and activity logs to quantify energy availability (EA), the LEA in Females Questionnaire (LEAF-Q), dual energy X-ray absorptiometry (DXA) scans to assess bone mineral density (BMD), and hormonal blood spot testing. (3) Results: Based on EA calculations, no athlete was at risk for LEA (females < 30 kcal·kg-1 FFM·day-1; and males < 25 kcal·kg-1 FFM·day-1; thresholds for able-bodied (AB) subjects). Overall, 78% of females were "at risk" for LEA using the LEAF-Q, and 67% reported birth control use, with three of these participants reporting menstrual dysfunction. BMD was clinically low in the hip (<-2 z-score) for 56% of female and 25% of male athletes (4) Conclusions: Based on calculated EA, the risk for RED-S appears to be low, but hormonal outcomes suggest that RED-S risk is high in this para-athlete population. This considerable discrepancy in various EA and RED-S assessment tools suggests the need for further investigation to determine the true prevalence of RED-S in para-athlete populations.

Post-Exercise Sweat Loss Estimation Accuracy of Athletes and Physically Active Adults: A Review.

The main purposes of this review were to provide a qualitative description of nine investigations in which sweat losses were estimated by participants following exercise and to perform a quantitative analysis of the collective data. Unique estimations (n = 297) were made by 127 men and 116 women after a variety of exercise modalities in moderate to hot environmental conditions. Actual sweat loss exceeded estimated sweat loss (p < 0.001) for women (1.072 ± 0.473 vs. 0.481 ± 0.372 L), men (1.778 ± 0.907 vs. 0.908 ± 0.666 L) and when all data were combined (1.428 ± 0.806 vs. 0.697 ± 0.581 L), respectively. However, estimation accuracy did not differ between women (55.2 ± 51.5%) and men (62.4 ± 54.5%). Underestimation of 50% or more of sweat losses were exhibited in 168 (54%) of estimation scenarios with heavier sweaters displaying a higher prevalence and trend of greater underestimations in general. Most modern guidelines for fluid intake during and between training bouts are based on approximate sweat loss estimation knowledge. These guidelines will likely have minimal efficacy if greater awareness of how to determine sweat losses and accurate recognition of sweat losses is not increased by coaches and athletes.

Hydration Status and Perception of Fluid Loss in Male and Female University Rugby Union Players.

Rugby union players are at risk for dehydration due to the high physiologic demand of the sport (~7.5 MJ/game). Dehydration could be due to lack of knowledge of fluid lost during activity. Therefore, the purpose of this study was to observe the hydration status and sweat loss estimations of male and female university rugby union players over three consecutive training sessions. Body mass, urine specific gravity (USG), and self-reported thirst scores were recorded pre and post training sessions. Sweat loss estimations were recorded post training session. After estimations, participants were shown his or her actual sweat loss in hopes of improving estimations over the three sessions. Paired t-tests were used to determine significance between pre and post training USG, thirst level and body mass for each day. A general linear mixed-effect model was used to determine significance of the difference between variables within gender and within days. Mean body mass changes did not exceed 2% lost for either gender on any of the three training sessions. Males significantly underestimated sweat loss by ~81% (p<0.01) after session one and improved estimations to ~36% after session three, however still significantly underestimated (p<0.01). Females also significantly underestimated sweat loss by ~64% on day one (p<0.01), and also improved estimations to ~60% on day three, however, still significantly underestimated (p<0.01). Results indicate that, on average, the participants remained in a euhydrated state throughout the training sessions. Findings also show that through education participants can improve perceptions of sweat loss to remain in euhydrated state.

Cocoa flavanol effects on markers of oxidative stress and recovery after muscle damage protocol in elite rugby players.

OBJECTIVES: Strenuous exercise can impair athletic performance due to muscular inflammation and oxidative stress. Antioxidants such as cocoa flavanols have been used as a supplement to prevent oxidative stress; however, the benefits of dietary antioxidants for athletic performance after muscle soreness (MS) is unclear. The purpose of this study was to examine the effects of cocoa flavanols after a MS inducing protocol. METHODS: In a randomized, double-blinded design, 13 male collegiate rugby players consumed either chocolate milk (CHOC) or chocolate milk with additional cocoa flavanols (CocoaCHOC) during a 7-d loading phase. MS was induced by a drop jump protocol on day 5 of the intervention. Athlete performance was assessed with vertical-jump and yo-yo tests and subjective measures of soreness 5 d before and 2 d post-MS protocol. Urinary markers of oxidative stress (isoprostanes) were assessed before and 48 h post-MS. RESULTS: No changes were observed between the groups over time for isometric torque (P = .63), vertical jump performance (P = .39), and yo-yo testing (P = .57) between the trials. No interaction was found in isoprostanes levels between the trials (CocoaCHOC baseline: 88 ± 0.38 pg/mL and 48 h post-MS: 81 ± 0.53 pg/mL; P = .82; and CHOC baseline: 98 ± 0.96 pg/mL and 48 h post-MS: 96 ± 0.38 pg/mL; P = .59). No main effect (treatment × time; P = .58) was observed for isoprostanes. Although not significant, the CocoaCHOC group ran 97 meters further than the CHOC group in the yo-yo test. CONCLUSIONS: Cocoa flavanols added to a post-exercise recovery beverage for 7 d has no oxidative stress or athletic performance benefits.

Effect of Vitamin D Supplementation on 25(OH)D Status in Elite Athletes With Spinal Cord Injury.

Recent studies suggest that a substantial proportion of athletes with spinal cord injury have insufficient 25(OH) vitamin D (25(OH)D) status, which may be associated with decreased muscle strength. This study consisted of two parts: (a) to examine the effects of a 12- to 16-week vitamin D3 supplementation protocol on 25(OH)D concentration and (b) to determine whether subsequent 25(OH)D status impacts muscle performance in elite athletes with spinal cord injury. Thirty-four members (age: 33 ± 15 years, weight: 69.6 ± 28.2 kg, and height: 170.2 ± 25.4 cm) of the U.S. and Canadian Paralympic program participated in the study. 25(OH)D concentrations and performance measures (handgrip strength and 20-m wheelchair sprint) were assessed pre- and postsupplementation. Participants were assigned a vitamin D3 supplementation protocol based on initial 25(OH)D concentrations. Participants with deficient 25(OH)D status (<50 nmol/L) received 50,000 IU/week for 8 weeks, and participants with insufficient status (50-75 nmol/L) received 35,000 IU/week for 4 weeks, after which both received a maintenance dose of 15,000 IU/week. Participants with sufficient status (>75 nmol/L) received the maintenance dose of 15,000 IU/week. 25(OH)D concentrations increased significantly (p < .001; 66.3 ± 24.3 nmol/L and 111.3 ± 30.8 nmol/L pre- and postsupplementation, respectively). About 26% of athletes had sufficient 25(OH)D concentrations presupplementation, and 91% had sufficient concentrations postsupplementation. About 62% of participants improved handgrip strength postsupplementation with no change in 20-m wheelchair sprint performance. The supplementation protocol was effective for achieving sufficient vitamin D concentrations in elite athletes with spinal cord injury.

Energy and Nutrient Issues in Athletes with Spinal Cord Injury: Are They at Risk for Low Energy Availability?

Low energy availability (LEA) and nutrient intake have been well studied in able-bodied athletes, but there is a lack of research examining these issues amongst athletes with spinal cord injury (SCI). To date, there have been no studies that have examined energy availability (EA) amongst this population. Furthermore, athletes with SCI may experience unique challenges around nutrition that may increase their risk of LEA. This review will evaluate the literature and assess whether this population is at risk for LEA. Due to the limited research on this topic, sedentary individuals with SCI and para athletes were also included in this review. Review of the current literature suggests that athletes with SCI may be at an increased risk for LEA. While research examining EA and risk of LEA in athletes with SCI is lacking, the number of athletes with SCI continues to increase; therefore, further research is warranted to assess nutrient and energy needs and their risk to this population.

Carbohydrate Mouth Rinse Improves Relative Mean Power During Multiple Sprint Performance.

Multiple investigations have confirmed carbohydrate mouth rinse (CMR) enhances high intensity endurance performance lasting under 1 hour, but the effects of CMR on high intensity intermittent exercise has received less attention. This study examined the effect of CMR on high intensity multiple sprint performances in a protocol designed to emulate a cyclocross or mountain biking event. Seven trained men (28.2 ± 6.8 years, 185 ± 9 cm, 85.3 ± 14.8 kg, VO2peak 51.4 ± 7.3 ml/kg*min-1) completed two, 48 min high intensity intermittent cycling protocols that consisted of 6 bouts of 5 min cycling at 50% VO2 peak followed by sets of three, 10-s Wingate sprints with 50 s of recovery between sprints. Prior to each set of Wingate sprints, either a 6.4% carbohydrate solution (CMR) or placebo (PLA) were rinsed for 10 s using a counterbalanced crossover design. There was a significant main effect (CMR 10.51 ± 0.82, PLA 10.33 ± 0.87 W/kg; p < 0.05 ES=0.21) for mean power, but post hoc tests only revealed statistically significant performance improvement with CMR during the 6th bout (CMR 10.5 ± 0.75, PLA 10.22 ± 0.92 W/kg; p = 0.01 ES=0.33). No treatment effect was exhibited for peak power, fatigue index, ratings of perceived exertion, or blood glucose. Most team sport situations provide multiple opportunities for access to beverages, but gastrointestinal distress associated with fluid intake may reduce desire for significant beverage consumption. Under such circumstances, a small but practical ergogenic advantage may be exhibited if the fluid rinsed in the mouth contains carbohydrates.

Nutrient Intake of Elite Canadian and American Athletes with Spinal Cord Injury.

The nutrient needs of athletes with Spinal Cord Injury (SCI) are dependent on their physiological alterations and training status. Limited research is available regarding dietary intake of elite athletes with SCI and possible nutrient deficiencies. Therefore, the purpose of this study was to examine dietary intake of elite athletes with SCI, and determine dietary intake inadequacies based on the Estimated Average Requirement (EAR) comparisons. Additionally, the average energy and macronutrient (carbohydrate, protein, and fat) intake was compared based on level of injury (C level, T1-T6, T7-T12, Lumbar). A total of 39 athletes with a SCI completed a self-reported 24 hour diet recall in autumn and 27 athletes returned to complete a second data collection period (winter). Nutrient inadequacy was estimated by the proportion of athletes with mean intakes below the EAR through the Research Solutions Food Processor Diet Analysis Software (ESHA). Although Macronutrients for both men and women were within acceptable macronutrient distribution range (AMDR) recommendations, low EAR's for various nutrients were consistently found for both men and women. No significant differences were found for energy or macronutrient intake between groups based on level of lesion. Further research is needed to examine nutrient intake using other methods of dietary assessment and to determine the factors that may lead to nutrient insufficiency among elite athletes with SCI.

Comparison of Circumference Measures and Height-Weight Tables With Dual-Energy X-Ray Absorptiometry Assessment of Body Composition in R.O.T.C. Cadets.

Mitchell, KM, Pritchett, RC, Gee, DL, and Pritchett, KL. Comparison of circumference measures and height-weight tables with dual-energy X-ray absorptiometry assessment of body composition in R.O.T.C. cadets. J Strength Cond Res 31(9): 2552-2556, 2017-Height-weight tables and circumference measures are used by the U.S. Army to predict body composition because they require little equipment or expertise. However, agreement between the Army's new 2002 circumference equation and an established laboratory technique has not been determined. The purpose of this study was to quantify agreement in body fat percentages between the Army's circumference measures (taping) and dual-energy X-ray absorptiometry (DXA); second to determine categorical agreement between height-weight tables and DXA. Male Reserve Officer Training Corps (R.O.T.C.) cadets (N = 23; 20.6 ± 1.6 years, 179.1 ± 6.6 cm; 81.4 ± 10.3 kg) were taped according to Army protocol to predict body fat. The % body fat prediction was compared with DXA through a Bland-Altman Plot with ±2-4% body fat established as a zone of agreement (ZOA). Thirteen out of 23 cadets fell outside the ZOA. No cadet was over the compliance threshold (20-22% fat) using the tape method, however, with DXA, 7 out of 23 cadets were noncompliant. Height-weight tables provided a moderate level of categorical agreement with DXA. The results depict poor agreement between taping and DXA, as taping generally underestimated % body fat. Compared with taping, height-weight tables were better able to identify excess fat weight.

25(OH)D Status of Elite Athletes with Spinal Cord Injury Relative to Lifestyle Factors.

BACKGROUND: Due to the potential negative impact of low Vitamin D status on performance-related factors and the higher risk of low Vitamin D status in Spinal Cord Injury (SCI) population, research is warranted to determine whether elite athletes with SCI have sufficient 25(OH)D levels. The purposes of this study were to examine: (1) the seasonal proportion of vitamin D insufficiency among elite athletes with SCI; and (2) to determine whether lifestyle factors, SCI lesion level, and muscle performance/function are related to vitamin D status in athletes with SCI. METHODS: Thirty-nine members of the Canadian Wheelchair Sports Association, and the US Olympic Committee Paralympic program from outdoor and indoor sports were recruited for this study. Dietary and lifestyle factors, and serum 25(OH)D concentrations were assessed during the autumn (October) and winter (February/March). An independent t-test was used to assess differences in 25(OH)D status among seasons, and indoor and outdoor sports in the autumn and winter, respectively. RESULTS: Mean ± SD serum 25(OH)D concentration was 69.6 ± 19.7 nmol/L (range from 30 to 107.3 nmol/L) and 67.4 ± 25.5 nmol/L (range from 20 to 117.3 nmol/L)in the autumn and winter, respectively. In the autumn, 15.4% of participants were considered vitamin D deficient (25(OH)D < 50 nmol/L) whereas 51.3% had 25(OH)D concentrations that would be considered insufficient (<80 nmol/L). In the winter, 15.4% were deficient while 41% of all participants were considered vitamin D insufficient. CONCLUSION: A substantial proportion of elite athletes with SCI have insufficient (41%-51%) and deficient (15.4%) 25(OH)D status in the autumn and winter. Furthermore, a seasonal decline in vitamin D status was not observed in the current study.

Enhancing Short-Term Recovery After High-Intensity Anaerobic Exercise.

This study examined the effects of antioxidant vitamins, ibuprofen, cold water submersion, and whey protein administered simultaneously on short-term recovery. Competitive athletes (n = 22) performed the protocol in 2 occasions (treatment and control) separated by 15 days in counterbalanced crossover design. Each occasion consisted of morning and afternoon sessions (AM and PM). In each session, participants performed 2 bouts of high-intensity anaerobic cycling separated by 30 minutes of rest. Each bout consisted of 3 Wingate tests (3 × 30-second Wingate tests) with 3 minutes of active recovery in between. Power output, rated perceived exertion (RPE), and pain scores were averaged and compared between the 2 sessions (AM vs. PM) and between the treatment vs. control (4 bouts). Creatine kinase (CK) levels were also measured 24 hours after the AM bout. Power output, CK, muscle soreness, and RPE were measured as recovery indices. Creatine kinase increased (p < 0.001) in both treatment and control 24 hours after the AM session. Performance results in the PM session for treatment/control were 832.5 ± 198.7/813.3 ± 187.6 W for peak power (PP), and 497.85 ± 120.7/486.1 ± 115 W for mean power (MP). Treatment was effective in maintaining MP (p = 0.034) in the PM sessions, but there was no significant effect of treatment on PP (p = 0.193), CK (p = 0.08), pain (p = 0.12), or RPE (p = 0.45). Treatment was helpful in protecting performance, but this was apparently not due to reduced muscle soreness or damage.

The effects of acute post exercise consumption of two cocoa-based beverages with varying flavanol content on indices of muscle recovery following downhill treadmill running.

Dietary flavanols have been associated with reduced oxidative stress, however their efficacy in promoting recovery after exercise induced muscle damage is unclear. This study examined the effectiveness of acute consumption of cocoa-flavanols on indices of muscle recovery including: subsequent exercise performance, creatine kinase, muscle tenderness, force, and self-perceived muscle soreness. Eight endurance-trained athletes (VO2max 64.4±7.6 mL/kg/min) completed a downhill running protocol to induce muscle soreness, and 48-h later completed a 5-K (kilometer) time trial. Muscle recovery measurements were taken at PRE, 24 h-POST, 48 h-POST, and POST-5K. Participants consumed 1.0 g of carbohydrate per kilogram of body weight of a randomly assigned beverage (CHOC: 0 mg flavanols vs. CocoaCHOC: 350 mg flavanols per serving) immediately after the downhill run and again 2 h later. The same protocol was repeated three weeks later with the other beverage. An ANOVA revealed no significant difference (p=0.97) between trials for 5 K completion time (CHOC 1198.3±160.6 s, CocoaCHOC 1195.5±148.8 s). No significant difference was found for creatine kinase (CK) levels (p=0.31), or muscle soreness (p=0.21) between groups over time. These findings suggest that the acute addition of cocoa flavanols to low-fat chocolate milk offer no additional recovery benefits.

Crossvalidation of two 20-m shuttle-run tests for predicting VO2max in female collegiate soccer players.

The aim of this study was twofold: (a) to compare the maximal attained speed (MAS) from the 20-m shuttle (MST) and 20-m square-shuttle (SST) tests and (b) to crossvalidate 2 equations for predicting maximal oxygen consumption (VO2max) that were previously developed from MST and SST in a group of female collegiate soccer players. Thirty-nine subjects (age: 20.1 ± 1.5 years) participated in the study. A maximal graded exercise treadmill test was used to measure VO2max. In addition, VO2max was predicted from the MAS obtained during MST ((pred)VO2maxMST) and SST ((pred)VO2maxSST) using previously developed equations. Measured VO2max for the group was 44.2 ± 3.3 ml·kg(-1)·min(-1). The MAS was 12.5 ± 0.6 km·h(-1) for MST and 13.3 ± 0.8 km·h(-1) for SST (p < 0.05). The prediction methods yielded a (pred)VO2maxMST of 49.6 ± 3.9 ml·kg(-1)·min(-1) and predVO2maxSST of 41.8 ± 3.1 ml·kg(-1)·min(-1), which were significantly different from measured VO2max (p < 0.05). The validity statistics revealed the following constant error (CE), correlation coefficient (r), standard error of estimate (SEE), and total error (TE) for (pred)VO2maxMST and (pred)VO2maxSST: CE = 5.35 ± 3.83, r = 0.45 (p < 0.05), SEE = 2.97 ml·kg(-1)·min(-1), TE = 6.39 ml·kg(-1)·min(-1); and CE = -2.43 ± 2.49, r = 0.69 (p < 0.05), SEE = 2.39 ml·kg(-1)·min(-1), TE = 3.43 ml·kg(-1)·min(-1), respectively. Residual plots indicated no proportional bias for either prediction model. The results of this study suggest that female collegiate soccer players had a higher MAS from SST compared with that from MST. In addition, SST appeared to be a more accurate predictor of VO2max than MST in the group of athletes.

Chocolate milk: a post-exercise recovery beverage for endurance sports.

An optimal post-exercise nutrition regimen is fundamental for ensuring recovery. Therefore, research has aimed to examine post-exercise nutritional strategies for enhanced training stimuli. Chocolate milk has become an affordable recovery beverage for many athletes, taking the place of more expensive commercially available recovery beverages. Low-fat chocolate milk consists of a 4:1 carbohydrate:protein ratio (similar to many commercial recovery beverages) and provides fluids and sodium to aid in post-workout recovery. Consuming chocolate milk (1.0-1.5•g•kg(-1) h(-1)) immediately after exercise and again at 2 h post-exercise appears to be optimal for exercise recovery and may attenuate indices of muscle damage. Future research should examine the optimal amount, timing, and frequency of ingestion of chocolate milk on post-exercise recovery measures including performance, indices of muscle damage, and muscle glycogen resynthesis.

Effects of forearm vs. leg submersion in work tolerance time in a hot environment while wearing firefighter protective clothing.

This study compared physiological responses and total work tolerance time following forearm submersion (FS) or leg submersion (LS) in cool water, after performing work in a hot environment while wearing fire fighting protective clothing (FPC). Participants walked at 3.5 mph on a treadmill in a hot environment (WBGT 32.8 ± 0.9°C) until a rectal temperature (T(rec)) of 38.5°C was reached. Participants were then subjected to one of two peripheral cooling interventions, in a counterbalanced order. Forearms or lower legs were submerged in water (16.9 ± 0.8°C) for a total of 20 min, followed by a work tolerance trial. Results indicated no significant difference (p = 0.052) between work tolerance time (LS = 21.36 ± 5.35 min vs. FS = 16.27 ± 5.56 min). Similarly, there was no significant difference for T(rec) (p = 0.65), heart rate (HR) (p = 0.79), mean skin temperature (T(sk)) (p = 0.68), and rating of perceived exertion (RPE) (p = 0.54). However, LS ratings of thermal comfort (RTC) at Minute 14 (p = 0.03) were significantly lower for LS (10 ± 1) vs. FS (12 ± 1). Results indicate little difference between FS and LS for physiological measures. Despite a lack of statistical significance a 5-min (24%) increase was found during the work tolerance time following LS.