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.

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.

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.

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.

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.

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.

Pacing accuracy in collegiate and recreational runners.

To examine runners' ability to produce a prescribed pace, we compared prescribed versus actual 400 m splits for collegiate (COL, n = 12) and recreational runners (REC, n = 16). Participants completed a VO(2max) trial and on a 400 m track, three 3,200 m time trials. During three subsequent sessions, participants completed 800 m warm-up; then, based on their fastest 3,200 m steady pace, subjects completed six laps total at three prescribed paces: (a) 2x 400 m at 7% slower than steady pace (SLO), (b) 2x 400 m at steady pace (AT) and (c) 2x 400 m at 7% faster than steady pace (FAS). Instructions were to complete the sets of two laps in prescribed times (e.g., 75 s per 400 m) (no feedback). Deviation scores (absolute value of difference: prescribed vs. actual time) (s) for each 400 m lap were compared using a 2 (group) x 3 (trial) repeated measures ANOVA. Main effects for deviations among trials SLO (7.3 +/- 6.5), AT (6.6 +/- 6.9) and FAS (6.2 +/- 5.7) were not significantly different (p > 0.05). However, group main effect for deviation scores was significantly (p < 0.05) lower (greater accuracy) for COL (2.9 +/- 3.2 s) versus REC (9.5 +/- 6.6 s). Deviation scores were also significantly different (p < 0.05) for SLO (COL: 3.1 +/- 2.7 s, REC: 10.4 +/- 6.7 s) and AT (COL: 1.9 +/- 1.9 s, REC: 10.1 +/- 7.2 s), with a trend for FAS (p = 0.06) (COL: 3.8 +/- 4.3 s, REC: 7.9 +/- 6.1 s). Bland-Altman plots showed better agreement (prescribed vs. actual) for COL. Experience and fitness of collegiate runners resulted in improved pacing accuracy.

Session RPE following interval and constant-resistance cycling in hot and cool environments.

PURPOSE: This study examined effects of heat gain, circulatory adjustment to temperature regulation (HR), and [La] consequent to interval (INT) and constant-load (CON) cycling on session RPE (S-RPE). METHODS: Male volunteers (N = 10) completed a cycle ergometer VO2peak test and then, in a randomized, counterbalanced order, four cycling bouts, including constant load (approximately 45% VO2peak) (CON) and interval (8 x 1 min at about 90% VO2peak, 1 min between intervals) (INT), in hot (approximately 32.5 WBGT) (HOT) and cool (approximately 21.0 WBGT) (COOL) environments. Trials included a standardized warm-up and cool-down (10 min each: 0 W, 60 rpm). Total external work was equated among all trials, with blood lactate ([La]), heart rate (HR), rectal temperature (Tre), and acute RPE recorded at 10, 13, 17, 21, 25, and 36 min. S-RPE was recorded 20 min after each session. RESULTS: HOT (CON and INT) resulted in significantly (P < 0.05) greater heat gain (Tre), HR, and RPE-O, whereas INT had significantly elevated [La] versus CON (HOT and COOL). HOT yielded significantly higher S-RPE versus COOL for CON (HOT = 5.6 +/- 2.1, COOL = 4.3 +/- 1.3) and INT (HOT = 7.0 +/- 1.9, COOL = 5.1 +/- 2.0). S-RPE was significantly higher for INT/HOT than CON/HOT. CONCLUSIONS: Heat gain and cardiac strain (Tre, HR) and [La]) were manipulated with environment and exercise type while holding total work constant. The added strain of HOT was reflected in elevated S-RPE for both CON and INT. S-RPE linkage with [La] was limited to HOT trials, indicating only a loose association. These data indicate that under the conditions of this study, S-RPE is similar to acute RPE in that no single mediator seems universally dominant.

Effects of caffeine on repetitions to failure and ratings of perceived exertion during resistance training.

CONTEXT: Ergogenic effects of caffeine on aerobic or endurance exercise are well documented. Conversely, the ergogenic value of caffeine on high-intensity, primarily anaerobic performance is not well understood even though the proposed mechanisms of action for caffeine permit a strong theoretical basis for application to this type of exercise. PURPOSE: This study examined effects of caffeine (Ca) on number repetitions (reps), ratings of perceived exertion (RPE), and peak heart rate (PHR) during resistance-training exercise with reps performed to volitional failure. METHODS: Subjects (N = 17) were tested for 10-rep maximum in bench press (BP) and leg press (LP). In sessions 2 and 3, Ca (approximately 6 mg/kg) or placebo (Pl) was ingested 1 hr beforehand in a double-blind manner and counterbalanced order. Subjects performed 3 sets to failure (BP and LP) with reps, PHR, and RPE recorded each set. Repeated-measures ANOVAs, 2 (trial) x 3 (set), were used to analyze dependent measures with the Tukey honestly significant difference used when necessary as the post hoc test. RESULTS: In BP, no significant differences (Ca vs Pl) were observed (reps, RPE, PHR). During set 3 of LP training, Ca was associated with significantly higher reps (12.5 +/- 4.2 vs 9.9 +/- 2.6) and PHR (158.5 +/- 11.9 vs 151.8 +/- 13.2). No significant RPE differences were found during LP. CONCLUSIONS: The findings of similar RPE concurrent with higher reps suggest that caffeine can blunt pain responses, possibly delaying fatigue in high-intensity resistance training. Ergogenic effects might be limited to the later sets in a resistance-training session. Further research is warranted regarding ergogenic effects of caffeine during resistance training and potential mechanisms of action.

RPE association with lactate and heart rate during high-intensity interval cycling.

PURPOSE: Physiological and perceptual measures during interval exercise are not well understood. The current study therefore examined the correspondence between RPE, HR, and blood lactate concentration ([La]) during interval cycling. METHODS: VO2peak and the 4.0 mmol x L(-1) lactate threshold were determined. In session 2, subjects (N = 12) warmed up (10 min, 0 W) and completed five 2-min intervals (INT) at >4 mmol x L(-1) workload, each separated by 3 min of recovery (REC) (60 rpm, 0 W). HR, RPE, and [La] were recorded at 10 min, at the conclusion of each INT, and each REC and 5- and 10-min recovery. RESULTS: Repeated-measures ANOVA showed [La], HR, and RPE increased significantly across time (INT and REC). At each time point, repeated-measures ANOVA was used to compare standardized data (alpha = 0.05). RPE (at INT) intensified concurrently with HR and [La] at INT. Correlations were significant for INT (P < or = 0.05) (HR-RPE: r = 0.63, [La]-RPE: r = 0.43). Similarly, RPE and HR for REC systematically increased with [La]. Correlations for REC were also significant (HR-RPE: r = 0.44, [La]-RPE: r = 0.34). Correlations were also significant for INT and REC combined (HR-RPE: r = 0.70, [La]-RPE: r = 0.22). CONCLUSIONS: INT and REC independently showed moderate correspondence for RPE-[La] and RPE-HR. However, tighter overall coupling of HR with RPE (vs [La] with RPE) and a dissociation between RPE-[La] suggest RPE during intervals of intense cycling were more sensitive to acute metabolic demand (evidenced by HR) versus [La].

Heart rate and ratings of perceived exertion during treadmill and elliptical exercise training.

Elliptical exercise has recently increased in popularity. However, little is known regarding heart rate and perceptual responses during this exercise mode even though such information is important with respect to prescribing and regulating exercise intensity. In the current study, heart rate and perceived exertion were compared between treadmill and elliptical exercise. During treadmill exercise (TM(EST)) participants estimated RPE-Overall as well as RPE-Legs and RPE-Chest. Two elliptical sessions followed: (1) RPE estimation during elliptical exercise (EL(EST)): HR (b/ min.) from TM(EST) was achieved during elliptical exercise, with participants estimating RPE-Overall, RPE-Legs, and RPE-Chest. (2) RPE production during elliptical exercise (EL(PROD)): RPE-Overall from TM(EST) was produced during elliptical exercise. There were no significant differences between modes for RPE-Overall (TM(EST): 11.2 +/- 2.2 vs EL(EST): 11.9 +/- 3.2) or RPE-Chest (TM(EST): 11.0 +/- 2.4 vs EL(EST): 11.7+/- 3.2). Mean RPE-Legs was significantly different (TM(EST): 11.2 +/- 2.4 vs EL(EST): 12.5 +/- 3.1). Heart rate was not significantly different between TM(EST) (163 +/- 16.6) and EL(PROD) (159 +/- 20.0). Analysis indicated elliptical exercise is perceived as more intense with respect to leg (RPE-Legs) exertion. Further, RPE-Overall appears effective for regulating heart rate during elliptical exercise.