Immediately Post Research Articles

The effects of type of recovery in resistance exercise on responses of platelet indices and hemodynamic variables.

To examine the effects of two different volume-matched resistance exercise (RE) recovery protocols (passive and active) on platelet indices and hemodynamic variables. Twelve Healthy participants (mean ± SD; 25 ± 3 yrs) completed a traditional resistance exercise (TRE) protocol that included three sets of six repetitions at 80% one repetition maximum (1RM) with two minutes passive recovery between sets, exercises and an interval resistance exercise (IRE) protocol that included three sets of six repetitions at 60%1RM followed by active recovery including six repetitions of the same exercise at 20%1RM. Blood samples for multiple platelet indices were taken before the protocols, immediately-post (IP), and after 1-hour recovery. Hemodynamic variables were measured before, IP, and every five minutes during recovery. Mean platelet volume and platelet large cell ratio P_LCR decreased from baseline to recovery. Heart rate (HR) and rate pressure product (RPP) were augmented at IP following IRE compared to TRE. HR was significantly elevated for 20 minutes after both RE protocols, and RPP recovered by five minutes. Systolic blood pressure was increased at IP compared to baseline and all recovery time points for both RE protocols. Our research demonstrated that both RE protocols, produced transient increases in platelet indices (MPV, and P_LCR) and hemodynamic variables (SBP, HR, and RPP), all of which returned to baseline within an hour. Notably, the IRE protocol elicited a greater increase in HR and RPP compared to the TRE protocol.

Evaluating the effects of PeakATP® supplementation on visuomotor reaction time and cognitive function following high-intensity sprint exercise.

The purpose of this study was to examine the effects of 14-days adenosine 5'-triphosphate (ATP) supplementation (PeakATP®) on reaction time (RT), multiple object tracking speed (MOT), mood and cognition. Twenty adults (22.3 ± 4.4 yrs., 169.9 ± 9.5 cm, 78.7 ± 14.6 kg) completed two experimental trials in a double-blind, counter-balanced, crossover design. Subjects were randomized to either PeakATP® (400 mg) or placebo (PLA) and supplemented for 14-days prior to each trial. During each trial, subjects completed a three-minute all-out test on a cycle ergometer (3MT), with measures of visuomotor RT [Dynavision D2 Proactive (Mode A) and Reactive (Mode B) tasks], MOT (Neurotracker), mood (Profile of Mood States Questionnaire; POMS) and cognition (Automated Neuropsychological Assessment Metrics; ANAM) occurring before (PRE), immediately post (IP) and 60 min post-3MT (60P). Subjects ingested an acute dose of the assigned supplement 30 min prior to completing PRE assessments for each trial. Trials were separated by a 14-day washout period. PeakATP® significantly attenuated declines in hits (p = 0.006, ηp2 = 0.235) and average RT (AvgRT, p = 0.006, ηp2 = 0.236) in Mode A, significantly improved AvgRT (p = 0.039, ηp2 = 0.174) in Mode B, and significantly reduced the total number of misses (p = 0.005, ηp2 = 0.343) in Mode B. No differences between treatments were noted for MOT, POMS or ANAM variables. In conclusion, these results indicate that PeakATP® maintains proactive RT and improves reactive RT following high-intensity sprint exercise suggesting that supplemental ATP may mitigate exercise induced cognitive dysfunction.

Circulating microRNA responses to acute whole-body vibration and resistance exercise in postmenopausal women

Evaluating alterations in circulating microRNA (c-miRNA) expression may provide deeper insight into the role of exercise in the attenuation of the negative effects of aging on musculoskeletal health. Currently, there are sparse data on c-miRNA responses to acute exercise in postmenopausal women. The purpose of this study was to characterize the effects of acute bouts of resistance exercise and whole-body vibration on expression of selected c-miRNAs in postmenopausal women aged 65-76 years (n=10). We also examined relationships between c-miRNAs and muscle strength and bone characteristics. This randomized crossover design study compared c-miRNA responses to a bout of resistance exercise (RE) (3 sets 10 reps 70% 1 repetition maximum (1RM), 5 exercises) and a bout of whole-body vibration (WBV) (5 sets 1min bouts 20Hz 3.38mm peak to peak displacement, Vibraflex vibration platform). DXA was used to measure body composition and areal bone mineral density (aBMD) of the total body, AP lumbar spine, and dual proximal femur. pQCT was used to measure tibia bone characteristics (4%, 38%, 66% sites). Blood samples were collected before exercise (Pre), immediately-post (IP), 60 minutes post (60P), 24 hours (24H), and 48 hours (48H) after exercise to measure serum miR-21-5p, -23a-3p, -133a-3p, -148a-3p (qPCR) and TRAP5b (ELISA). There was a significant modality × time interaction for c-miR-21-5p expression (p=0.019), which decreased from 60P to 24H after WBV only. TRAP5b serum concentrations significantly increased IP then decreased below Pre at 24H for both WBV and RE (p<0.01). Absolute changes in TRAP5b were negatively correlated with c-miR-21-5p fold changes (r= -0.642 to -0.724, p<0.05) for both exercise modalities. There were significant negative correlations between baseline c-miRNAs and bone status variables (r= -0.639 to -0.877, p<0.05). Our findings suggest that whole-body vibration is a sufficient mechanical stimulus for altering c-miR-21-5p expression, whereas a high intensity resistance exercise protocol did not elicit any c-miRNA responses in postmenopausal women. Increases in the bone resorption marker, TRAP5b, were associated with greater downregulation of c-miR-21-5p expression.

Changes In Cognitive Function, Neurotrophin Concentrations, And Both Brain And Systemic Inflammatory Markers Following A Game Of American Football

PURPOSE: This investigation examined the effect of a simulated American football game on cognitive function, neurotrophin concentrations and markers of both systemic and brain inflammation. METHODS: Members of the Israel national team players (six linemen and nine skill position players) were examined one-week prior to (PRE), immediately-post (IP) and 24-hours-post (24P) game. Blood was obtained and cognitive function was measured at each assessment. RESULTS:No head injuries to any of the players participating in the study occurred. Significant (p < 0.001) decreases in acute memory and a trend (p = 0.066) towards a decrease in delayed memory were noted at IP. Significant negative correlations were observed between playing time (number of plays) and concentration changes from PRE to IP (r = -0.801, p = 0.001) and from PRE to 24P (r = -0.549, p = 0.034). All cognitive function measures returned to PRE levels by 24P. Increases from PRE were noted in TNF-α (p = 0.041) at IP, and in BDNF (p = 0.009) and CRP (p = 0.019) concentrations at 24P. Circulating CRP concentrations, and the cytokine markers IL-4, IL-6, IL10 and TNF-α, were significantly elevated in linemen compared to skill players. Brain inflammatory markers (S100B and GFAP) and total tau protein (a marker of brain injury) were not elevated from PRE. No change from PRE was noted in either myoglobin or creatine kinase-mm concentrations. CONCLUSIONS: Muscle damage and inflammatory marker responses observed from the scrimmage game were consistent with muscle desensitization associated with football participation. In addition, the systemic inflammatory marker results observed in linemen were suggestive of chronic low-grade inflammation.

Examination of Cognitive Function, Neurotrophin Concentrations, and both Brain and Systemic Inflammatory Markers Following a Simulated Game of American Football.

Hoffman, JR, Ostfeld, I, Zamir, A, Amedi, R, Fonville, TR, Horstemeyer, MF, and Gepner, Y. Examination of cognitive function, neurotrophin concentrations, and both brain and systemic inflammatory markers following a simulated game of American football. J Strength Cond Res 36(3): 686-694, 2022-This investigation examined the effect of a simulated American football game on cognitive function, neurotrophin concentrations, and markers of both systemic and brain inflammation. Members of the Israel national team (6 linemen and 9 skill position players) were examined 1 week before (PRE), immediately post (IP) and 24-hour post (24P) game. Blood was obtained, and cognitive function was measured at each assessment. No head injuries to any of the players participating in the study occurred. Significant (p < 0.001) decreases in acute memory, and a trend (p = 0.066) toward a decrease in delayed memory was noted at IP. Significant negative correlations were observed between playing time (number of plays) and concentration changes from PRE to IP (r = -0.801; p = 0.001) and from PRE to 24P (r = -0.549; p = 0.034). All cognitive function measures returned to PRE levels by 24P. Increases from PRE were noted in tumor necrosis factor-alpha (TNF-α) (p = 0.041) at IP and in brain-derived neurotrophic factor (p = 0.009) and C-reactive protein (CRP) (p = 0.019) concentrations at 24P. Circulating CRP concentrations and the cytokine markers, interleukin (IL)-4, IL-6, IL-10, and TNF-α, were significantly elevated in linemen compared with skill players. Brain inflammatory markers (S100B and glial fibrillary acidic protein) and total tau protein (a marker of brain injury) were not elevated from PRE. No change from PRE was noted in either myoglobin or creatine kinase-MM concentrations. In conclusion, muscle damage and inflammatory marker responses observed from the scrimmage game were consistent with muscle desensitization associated with football participation. In addition, the systemic inflammatory marker results observed in linemen were suggestive of chronic low-grade inflammation.

Change in measures of moral function following acute bouts of Marine Corps Martial Arts Training.

The Marine Corps Martial Arts Program (MCMAP) was developed to prepare Marines for complex battlefield situations that include hand-to-hand combat and ethical decision making. The objective of this study was to quantify changes in ethical decision-making following MCMAP training. Fifty-five, active duty, newly enlisted U.S. Marines (Males: n=37; age=19±1years; height=176±7cm; mass=74±7 kg; Females: n=18; age=20±2years; height=164±6cm; mass=61±6 kg) volunteered for this investigation and were assessed three times over 6weeks, with 3weeks between each visit, using serial blood samples for cortisol, norepinephrine, and epinephrine collected before training and during recovery [Immediate Post (IP), 15, 30, 45 and 60min]. The Moral Functioning Continuum was used to quantify moral function before training, IP, 30, and 60min post. Moral intention exhibited an acute response to training with significantly impaired decision making immediately post training. Moreover, both moral intention and moral judgement worsened over the visits suggesting a chronic impairment related to time in training suggesting a functional change in ethical decision-making following acute bouts of MCMAP.

Effect of rest period configurations on systemic inflammatory response in resistance-trained women

ABSTRACT This investigation examined the effect of rest- redistribution (RR) on the circulating cytokine response to resistance exercise in resistance- trained women. Participants (n = 13; 24 ± 4y; 65.0 ± 10.6 kg; 160.5 ± 5.1 cm) completed two sessions of back squats at 70% of 1- repetition maximum: Traditional sets (TS: 4x10, 120-s inter- set rest) and RR (4x 2x5) with 30-s intra- set rest after 5 repetitions and 90-s inter- set rest. Serum creatine kinase (CK), IL-1β, IL-6, IL-8, IL-10, IL-15, and IL-6/IL-10 were determined before (PRE), immediately- post (IP), and 5, 15, 30, 60 min, 24 h, and 48 h post- exercise. CK increased significantly (p < 0.05) from PRE through 24 h for TS and through 48 h for RR. IL-15 was greater for RR than TS at 48 h. A condition effect was found for IL-10 and IL-6/IL-10 with a lower IL-10 and a greater IL-6/IL-10 for RR. A time effect demonstrated that IL-1β and IL-10 peaked at IP. IL-8 was increased from 5 min to 60 min and 24 h. IL-6/IL-10 was increased from PRE to 30 min, 60 min, and 24 h. These results suggested that rest period configuration- specific differences exist for the inflammatory response in trained women during intramuscular homoeostatic disruption.

Impact of Varying Dosages of Fish Oil on Recovery and Soreness Following Eccentric Exercise.

Fish oils (FOs) are rich in omega-3 long-chain polyunsaturated fatty acids, which have been purported to enhance recovery of muscular performance and reduce soreness post-exercise. However, the most effective FO dose for optimizing recovery remains unclear. The purpose of this investigation was to examine the effect of FO supplementation dosing on the recovery of measures of muscular performance, perceived soreness, and markers of muscle damage following a rigorous bout of eccentric exercise. Thirty-two college-aged resistance-trained males (~23.6 years, 71.6 kg, 172.1 cm) were supplemented with 2, 4, 6 g/day (G) FO or placebo (PL) for ~7.5 weeks. Following 7 weeks of supplementation, pre-exercise (PRE) performance assessments of vertical jump (VJ), knee extensor strength, 40-yard sprint, T-test agility, and perceived soreness were completed prior to a bout of muscle-damaging exercise and were repeated immediately post (IP), 1-, 2-, 4-, 24-, 48-, and 72-h (H) post-exercise. Repeated measures analysis of variance indicated a treatment × time interaction (p < 0.001) for VJ and perceived soreness, but no group differences were observed at any time point. VJ returned to PRE (54.8 ± 7.9 cm) by 1H (51.8 ± 6.5 cm, p = 0.112) for 6G, while no other groups returned to baseline until 48H. Lower soreness scores were observed in 6G compared to PL at 2H (mean difference [MD] = 2.74, p = 0.046), at 24H (MD: 3.45, p < 0.001), at 48H (MD = 4.45, p < 0.001), and at 72H (MD = 3.00, p = 0.003). Supplementation with 6G of FO optimized the recovery of jump performance and muscle soreness following a damaging bout of exercise.

C-mirna Expression Responses To Whole-body Vibration And Resistance Exercise In Postmenopausal Women

Circulating microRNAs (c-miRNA, miR) are potential biomarkers for age-related changes in musculoskeletal function. There is a paucity of data on c-miRNA responses to exercise, especially in postmenopausal women (PMW). Evaluating alterations in the expression of c-miRNA may provide deeper insight into the benefits of exercise for bone health in aging populations. PURPOSE: The purpose of this study was to characterize the effects of acute bouts of resistance exercise (RE) and whole-body vibration (WBV) on selected c-miRNAs that regulate bone metabolism (miR-21-5p, -23a-3p, -133a-3p, -148a-3p) in PMW (n=10). METHODS: Subjects performed a high intensity RE condition and a WBV condition in random order. RE consisted of 3 sets, 10 reps, 70% 1RM for leg press, shoulder press, lat pulldown, leg extension, and hip adduction isotonic exercises. For WBV, 5-1 min bouts were performed (20 Hz, 3.38 mm peak-to-peak displacement) each separate by 1 min rest on a Galileo vibration platform. Morning blood samples after an overnight fast were collected pre, immediately-post (IP), 60 min, 24 hrs, and 48 hrs after exercise to measure c-miRNA and TRAP5b. C-miRNA expression was corrected for plasma volume (PV) shifts using the equation: %ΔPV = (log(100)/(log(100) – log(Hct Pre)) * log(100)*((log(Hct Pre) – log(Hct Post))/log(Hct Post)). The correction factor was subtracted from the Cq values for each exercise sample. RESULTS: PV significantly decreased for both conditions at IP (p=0.04), thus serum variables were corrected for PV shifts. There was a significant condition × time interaction for miR-21 (p=0.019), which decreased in relative expression from 60p (1.61 ± 0.31) to 24h (0.80 ± 0.16) after WBV but not after RE. MiR-23a-3p, -133a-3p, -148a-3p showed no significant expression changes for either exercise condition. TRAP5b concentrations significantly decreased 24h (WBV -7.56% ± 5.27, RE -3.44% ± 4.33) after exercise (p<0.01) even after correcting for PV shifts (p<0.01). CONCLUSION: C-miR-21-5p was downregulated at 24 hrs in response to an acute bout of WBV. Both types of exercise also decreased serum TRAP5b 24 hrs post-exercise, indicating decreased bone resorption. This is the first known study to correct c-miRNA expression for PV shifts.

Acute Protease Supplementation Does Not Alter The Endocrine Response To Resistance Exercise In Trained Males

Proteases are enzymes which aid in the hydrolysis of proteins. Previous work has demonstrated protease supplementation may enhance recovery after high-intensity exercise by decreasing muscle damage and inflammation. While the mechanisms involved are not fully understood, it has been suggested that protease supplementation may alter the endocrine response to exercise, promoting a more favorable recovery state. PURPOSE: To determine if protease supplementation immediately after an exercise session influences circulating testosterone, cortisol, insulin, insulin-like growth factor-1 (IGF-1), and growth hormone (GH) concentrations. METHODS: Ten resistance trained males (24.1±4.1yr, 69.6±6.8 kg 179±8.6 cm) completed 3 acute lower-body resistance exercise sessions consisting of 4 sets of leg press and leg extension in a randomized, crossover fashion. Each exercise was performed at 75% of participant’s previously determined one repetition maximum, for 8-10 repetitions, with 90 seconds of rest between sets. Following the exercise session, participants consumed one of 3 treatments (W: 26g whey; PW: 26g whey + 250mg of a protease enzyme blend; PL: non-caloric control). Blood draws were obtained at baseline (BL), immediately-post (IP), 1-hour (1H) and 3-hours post-exercise (3H) and analyzed for testosterone, cortisol, insulin, IGF-1, and GH. Data for each hormone were analyzed with a 2-way repeated measures analysis of variance (ANOVA), while area under the curve (AUC) values were analyzed with a one-way ANOVA. RESULTS: Significant main effects for time (p<0.05) were observed for all hormones. There was a significant decrease in testosterone at IP (p=0.007), 1H (p<0.001), and 3H (p<0.001). There was a significant decrease in cortisol at all time points (p<0.001) compared to BL. There were significant increases in insulin, IGF-1, and growth hormone at all time points (p<0.001) following exercise. Additionally, no interaction for any hormone concentrations or AUC values were seen between treatments in this study. CONCLUSION: There were no differential effects of W or PW on the post-exercise endocrine response compared to PL. Therefore, neither protease nor protein supplementation appear to alter endocrine response to resistance exercise in trained males. Supported by Deerland Enzymes, Kennesaw, GA

The Effect of ProHydrolase® on the Amino Acid and Intramuscular Anabolic Signaling Response to Resistance Exercise in Trained Males

This double-blind study examined effects of a protease enzyme blend (Prohydrolase®) added to whey protein on post-resistance exercise aminoacidemia and intramuscular anabolic signaling were investigated in ten resistance-trained males. Participants completed 4 sets of 8–10 repetitions in the leg press and leg extension exercises at 75% of 1-repetition maximum. Participants then consumed either 250 mg of Prohydrolase® + 26 g of whey protein (PW), 26 g whey alone (W), or non-nutritive control (CON) in counterbalanced order. Blood samples were obtained prior to exercise (baseline) and then immediately-post (IP), 30-, 60-, 90-, 120-, and 180-min post-exercise. Muscle biopsies were taken at baseline, 1-h (1H), and 3-h (3H) post-exercise. Phosphorylation of AKTSer437 was decreased (3H only: p < 0.001), mTORSer2448 was increased (1H: p = 0.025; 3H: p = 0.009), and p70S6KThr412 remained unchanged similarly for each condition. Plasma leucine, branch-chained amino acids, and essential amino acid concentrations for PW were significantly higher than CON (p < 0.05) at 30 min and similar to W. Compared to IP, PW was the only treatment with elevated plasma leucine levels at 30 min (p = 0.007; ∆ = 57.8 mmol/L, 95% Confidence Interval (CI): 20.0, 95.6) and EAA levels at 180 min (p = 0.003; ∆ = 179.1 mmol/L, 95% CI: 77.5, 280.7). Area under the curve amino acid analysis revealed no differences between PW and W. While no different than W, these data indicate that PW was the only group to produce elevated amino acid concentrations 30-min and 180-min post-ingestion.

Mood State Changes Accompanying the Crossfit Open™ Competition in Healthy Adults.

Background: Specific mood states were examined during the CrossFit Open, a consecutive 5-week fitness competition involving five separate CrossFit® workouts, to determine whether the unique design or strenuous workouts of the competition resulted in acute and/or chronic mood state alterations. Methods: Participants (n = 8) completed the Profile of Mood States (POMS) questionnaire one-week prior to the competition (baseline), prior to (PRE), immediately post (IP), 30-min post- (30P) and 60-min post-workout (60P) each week. Tension, depression, anger, confusion, fatigue and vigor were derived from the POMS, as was Total Mood Disturbance (TMD) and an Energy Index (EI). Results: Workout intensity exceeded 93% HRmax each week. No differences were observed between baseline and PRE-workout mood states across weeks, indicating little effect of the unique competition design. Significant (week x time) interactions were observed for TMD (p = 0.037), EI (p = 0.038) and fatigue (p = 0.005). Acute mood state fluctuations were consistent across each week, where mood states improved to and beyond PRE values 60-min post-workout. Conclusions: In competitors, the differences in workout design between each week did not influence mood states. This may be related to adaptation to this style of training, while the acute mood state alterations are likely due to the workout intensity.

Changes in CRP and TNF‐a after Runs at Different Intensities in Smokers Following Two Hour Cessation

The purpose of this study was to examine changes in C‐reactive protein (CRP) and TNF‐α from blood samples before and after exercise at different intensities in smokers (SM) and non‐smokers (NS) after a 2 hour smoking cessation. Our laboratory previously reported large differences in CRP and TNF‐α at Pre between SM and NS. Furthermore, there were more profound disturbances in SM following three runs at different intensities approximately 30 minutes after smoking cessation before each run (EB 2015, Boston). The previous findings indicated that SM responded more sensitively to relatively equal intensity of exercise, which suggested that high intensity aerobic exercise should be avoided in SM in the beginning phase of exercise training.MethodsA total of eighteen physically inactive subjects (eight SM and ten NS) aged 20 to 27 were recruited. Smokers were accepted if their level of exhaled carbon monoxide (eCO) was greater than 16 ppm. Each subject completed three treadmill runs at different intensities in a random order (55%, 65%, and 75% of VO2max). Running distance for all three runs was equivalent to 35‐min run at 65% VO2max. Smokers had a 2 hour smoking cessation before each run. Blood samples were collected before (Pre), immediately post (IP), and an hour following each run (1h Post).ResultsPre‐exercise CRP levels were higher in SM as compared to the NS. (2.291±.27 mg/L Vs. 2.082±.25, mean±SE, P = 0.042). As compared to Pre, no significant changes were found in CRP at IP and 1h Post following runs at three different intensities in both SM and NS. TNF‐α showed higher pre‐exercise levels in SM compared to NS (32.565±4.28 mg/L vs. 27.732±3.34, P=0.027). TNF‐α was significantly increased at IP following 75% of VO2max run in both SM and NS (SM: 32.657±4.36 → 38.797±6.33, P=0.013; NS: 27.694±3.26 → 33.466±4.35, P=0.019), but not significantly changed at IP following 55% and 65% of VO2max runs.ConclusionFindings of the current study revealed a dose‐response relationship for CRP and TNF‐a in SM and NS. The patterns of changes corresponded with previous presentation (EB, 2015) with a 30 minute smoking cessation; however, the differences between SM and NS were much smaller in this study suggesting that smokers may need to avoid cigarette smoking before exercise to minimize immune disturbance caused by combined stress from exercise and chronic smoking.Support or Funding InformationThis study was supported by Texas A&amp;M International University Research Grant.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Comparisons in the Recovery Response From Resistance Exercise Between Young and Middle-Aged Men.

Gordon, JA III, Hoffman, JR, Arroyo, E, Varanoske, AN, Coker, NA, Gepner, Y, Wells, AJ, Stout, JR, and Fukuda, DH. Comparisons in the recovery response from resistance exercise between young and middle-aged men. J Strength Cond Res 31(12): 3454-3462, 2017-The purpose of this study was to compare the effects of a bout of high-volume isokinetic resistance exercise protocol (HVP) on lower-body strength and markers of inflammation and muscle damage during recovery between young and middle-aged adult men. Nineteen recreationally trained men were classified as either a young adult (YA: 21.8 ± 2.0 years; 90.7 ± 11.6 kg) or a middle-aged adult (MA: 47.0 ± 4.4 years; 96.0 ± 21.5 kg) group. The HVP consisted of 8 sets of 10 repetitions, with 1 minute of rest between each set, performed on an isokinetic dynamometer at 60°·s. Maximal voluntary isometric contractions and isokinetic peak torque (PKT) and average torque (AVGT) (measured at 240° and 60°·s, respectively) were assessed at baseline (BL), immediately post (IP), 120 minutes, 24, and 48 hours after HVP. Blood was obtained at BL, IP, 30, 60, 120 minute, 24, and 48 hours after HVP to assess muscle damage and inflammation. All performance data were analyzed using repeated measures analysis of covariance, whereas all inflammatory and muscle damage markers were analyzed using a 2-way (time × group) repeated measures analysis of variance. Results revealed no between-group differences for PKT, AVGT, or rate of torque development at 200 ms (RTD200). No between-group differences in myoglobin, creatine kinase, C-reactive protein, or interleukin-6 were observed. Although BL differences in muscle performance were observed between YA and MA, no between-group differences were noted in performance recovery measures from high-volume isokinetic exercise in recreationally trained men. These results also indicate that the inflammatory and muscle damage response from high-volume isokinetic exercise is similar between recreationally trained, young, and middle-aged adult men.

Cardiovascular Response of an Acute Exergame Session in Prepubertal Obese Children.

We aimed to analyze the acute autonomic response of obese and eutrophic prepubertal boys to an exergame (EXG) session. Nine eutrophic (8.89 ± 2.71 years of age and 16.42% ± 6.30% body fat) and nine obese boys (8.70 ± 1.16 years of age and 40.76% ± 4.2% body fat) participated. Nutritional state was determined using World Health Organization guidelines. Variables were collected at rest, immediately post (IP), and 60 minutes after a 20 minutes EXG session. Autonomic nervous system (ANS) activity was assessed using heart rate variability in time and frequency domains, and data were analyzed using Shapiro-Wilk and ANOVA tests with Tukey post hoc. The obese group demonstrated an increased sympathetic activity at rest when compared with the eutrophic group (P < 0.05). The obese group also demonstrated an increased parasympathetic activity 60 minutes after the EXG session when compared with the eutrophic group (P < 0.05). We concluded that an acute session of EXG promoted ANS super compensation. We encourage research on chronic ANS response to EXG.

Comparison of Mood Response Through Five Weeks of a High Intensity Functional Training Competition

Mood is known to be affected by exercise, as well as the predictability of an event. By design, high-intensity functional training (HIFT) incorporates a wide variety of exercise modalities. Further, competitive HIFT events generally incorporate a unique and unpredictable combination of fitness challenges that may elicit varying mood responses. PURPOSE: Examine mood prior to and following 5 unique, competitive HIFT events during a worldwide fitness competition. METHODS: Physically active adults (N=11; 34.9 ± 5.1 years, 77.9 ± 15.1 kg, 166.1 ± 10.6 cm) with HIFT experience (≥6 months) completed a baseline (BL) Profile of Mood States (POMS) questionnaire the week prior to the HIFT competition. During each week of the 5-wk competition, the competitors completed a unique HIFT fitness challenge. For each challenge, the POMS was completed prior to (PRE), immediately post (IP), 30-min post- (30P), and 60-min post-exercise (60P). The POMS yields measures of tension, depression, anger, confusion, fatigue (FAT), and vigor (VIG). Additionally, Total Mood Disturbance (TMD; sum of other 5 subscales minus VIG) and Energy Index (EI; VIG - FAT) were also calculated and analyzed. RESULTS: Repeated measures analysis of variance revealed no differences between BL and PRE values across weeks. Week (1-5) x Time (PRE, IP, 30P, 60P) interactions were observed for EI (P=0.025) and FAT (P=0.002). Compared to Week 5, EI was higher (increased VIG and/or decreased FAT) in Week 3 at 30P (Wk3: 12.3 ± 3.6; Wk5: 4.0 ± 5.4, P=0.003), and higher than Wk1 (P=0.005) and Wk3 (P=0.005) at 60P (Wk1: 14.8 ± 8.7; Wk3: 11.6 ± 4.0; Wk5: 6.0 ± 5.4). Compared to Wk3, FAT was significantly greater at Wk1 (P=0.005), Wk4 (P=0.001), and Wk5 (P=0.008) at IP (Wk1: 10.3 ± 4.0; Wk3: 4.4 ± 5.2; Wk4: 9.1 ± 5.9; Wk5: 10.4 ± 7.3). No other significant interactions were observed between weeks. CONCLUSION: The unique design of the HIFT competition did not seem to impact pre-exercise mood, but the different workouts resulted in differing mood responses, particularly for vigor and fatigue.

Comparison of Bioimpedance and Underwater Weighing Body Fat Percentage Before and Acutely After Exercise at Varying Intensities.

Nickerson, BS, Esco, MR, Kliszczewicz, BM, and Freeborn, TJ. Comparison of bioimpedance and underwater weighing body fat percentage before and acutely after exercise at varying intensities. J Strength Cond Res 31(5): 1395-1402, 2017-The purpose of this study was to compare single-frequency bioelectrical impedance analysis (BIA) and bioimpedance spectroscopy (BIS) with underwater weighing (UWW) body fat percentage (BF%) before (PRE), immediately post (IP), and 60 minutes post (60P) an acute bout of moderate and vigorous aerobic exercise. Nine men (age = 24.6 ± 3.7 years) volunteered for this study. Subjects visited the laboratory on 3 separate occasions. Testing included two 30-minute exercise sessions at 60 and 80% heart rate reserve (HRR) and a 30-minute control (CON) trial. The constant error (CE) was significantly higher for BIA at each time point and exercise session (CE = 3.0-4.9% for 60% HRR; 2.5-4.7% for 80% HRR). Conversely, BIS yielded a nonsignificant CE at each time point and exercise session (CE = -0.9 to 1.1% for 60% HRR; -0.3 to 1.2% for 80% HRR). The standard error of estimate (SEE) for both exercise sessions ranged from 2.7 to 3.1% and 3.8-4.3% for BIA and BIS, respectively. The 95% limits of agreement were narrower for BIA (60% HRR = ±5.5 to 7.8%; 80% HRR = ±6.6 to 8.5%) than BIS (60% HRR = ±8.4 to 9.4%; 80% HRR = ±8.1 to 10.2%). Results indicate that BIS can be used for mean group BF% in men at PRE, IP, and 60P time periods. However, BIA yielded a lower SEE and 95% limits of agreement than BIS. Therefore, BIA provides better individual estimates of BF% in men, but the CE should be taken into consideration.

Six Grams of Fish Oil Supplementation Mitigates Perceived Muscle Soreness Following Acute Resistance Exercise

High-intensity eccentric exercise is known to cause skeletal muscle damage and microstructural changes to muscle tissue with an associated inflammatory response. Previous research demonstrates increased pro-inflammatory cytokine and prostaglandin concentrations are linked with perceived muscle soreness. The omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), commonly found in fish oil supplements, exhibit anti-inflammatory properties that have been reported to attenuate the overall perception of muscle soreness. PURPOSE: To investigate the dose-response effect of fish oil (FO) supplementation on the magnitude and time-course of post-eccentric resistance exercise muscle soreness. METHODS: Thirty-two, college-aged, resistance-trained males (n = 16; 23.8 ± 2.7 years, 81.5 ± 9.9 kg, 175.7 ± 4.5 cm, 16.3 ± 3.6 %) and females (n = 16; 23.4 ± 3.1 years, 61.7 ± 7.2 kg, 170.4 ± 6.2 cm, 23.6 ± 5.0 %) completed a double-blind placebo controlled 7-week supplementation period of either: 2.0, 4.0, or 6.0 g·d-1 FO or placebo (PL). Subsequently, participants completed a muscle damaging resistance exercise protocol (10 sets of 8 four-second eccentric squats at 70% one-repetition maximum and 5 sets of 20 split-squat jumps). Perceived muscle soreness (PS; 0–10 cm scale) was measured pre-exercise (PRE), immediately post (IP), as well as 1, 2, 4, 24, 48, and 72 hours (h) post-exercise. RESULTS: Repeated measures analysis of variance revealed a group x time interaction for PS (p < 0.001), where compared to PL, lower PS scores were observed at IP for 6 g·d-1 (mean difference: 4.0 cm, p = 0.024), at 1h for 6 g·d-1 (mean difference: 2.74 cm, p = 0.046), at 24h for 4 g·d-1 (mean difference: 2.38 cm, p = 0.023), and 6 g·d-1 (mean difference: 3.45 cm, p < 0.001), at 48h for 6 g·d-1 (mean difference: 4.45 cm, p < 0.001), and at 72h for 6 g·d-1 (mean difference: 3.0 cm, p = 0.003). Other group differences were variable by time point. CONCLUSIONS: These data indicate that supplementation with 6 g·d-1 of FO is effective at attenuating PS following damaging eccentric resistance exercise for up to 72h. Supported by the International Society of Sports Nutrition and MusclePharm Grant

Comparison Between High‐Intensity and High‐Volume Resistance Training on the Acute Myokine Response in Resistance Trained Men

Secreted protein acidic and rich in cysteine (SPARC) and musclin are myokines implicated in glucose uptake signaling. SPARC has been shown to increase expression of GLUT4 on myocytes, while musclin has been shown to inhibit insulin signaling, suggesting a possible increased reliance on fat metabolism during exercise. SPARC and musclin concentrations have been shown to increase in response to acute exercise. However, the effect of different resistance training paradigms on changes in the plasma concentrations of these myokines remain unknown. The purpose of this study was to examine the acute response of these myokines following two commonly utilized resistance training paradigms. Twenty resistance trained men volunteered to participate in this study. Following a two‐week preparatory period, participants were randomly assigned to either a high‐intensity (HI; n=10, 22.6±2.3 y; 87.0±15.1 kg; 1.79±0.05m) or high‐volume (HV; n=10, 24.5±2.6 y; 89.5±12.9 kg; 1.66±0.34m) group. Prior to the first training session, participants completed an acute lower‐body exercise protocol. The HI protocol consisted of four sets of 3–5 reps at 90% 1RM, while the HV protocol consisted of four sets of 10–12 reps; 70% 1RM. Blood samples were collected at baseline (BL), immediately post (IP), 30 minutes' post (30P), and 60 minutes' post (60P) exercise during the acute exercise protocol. Following the acute exercise protocol, participants then completed 7 weeks of training under their respective exercise paradigms. The acute exercise protocol was repeated following the training intervention. Data was analyzed using a 2×2×4 (group [HI vs. HV] × training [pre vs. post] × time [BL‐60P]) repeated measures ANOVA. No significant group × time × training, group × time, or group × training interactions were observed for SPARC (p&gt;0.05). However, a significant training × time interaction was observed (p=0.016). With both groups combined, circulating concentrations of SPARC were significantly lower at 60P post‐training compared to pre‐training (p=0.001; mean diff: −29.5 ± 30.9 ng/mL). Further, a trend was observed towards a post‐training decrease in SPARC at 30P (p=0.089; mean diff: −11.3 ± 27.4 ng/mL). No significant group × time × training, group × time, group × training, or training × time interactions were observed for musclin. However, a significant main effect for training was observed (p=0.031) indicating an attenuation of the musclin response post‐training compared to pre‐training. A significant main effect for time was also observed for musclin (p=0.007). Post‐hoc analysis revealed that musclin concentrations were significantly lower at 60P compared to BL (20.9 ± 75.3 ng/mL), irrespective of group or training. Results of this study indicated that the temporal SPARC response to resistance exercise is attenuated following 7‐weeks of resistance training, with no differences between HI and HV training. A decline in musclin concentrations was observed at 60P relative to BL, irrespective of group or training. Further, musclin concentrations were lower post‐training compared to pre‐training.

Revisiting the Force-Joint Angle Relationship After Eccentric Exercise.

The purpose of this study was to evaluate force-angle curve fitting techniques pre-eccentric exercise, quantify changes in curve characteristics postexercise, and examine the relationship between curve changes and markers of muscle damage. Fourteen males unaccustomed to eccentric exercise performed 60 eccentric muscle actions of the elbow flexors. Maximal voluntary isometric force was measured throughout a range of angles pre- (Pre1 and Pre2), immediately post (IP), and 1, 2, 4, and 7 days postexercise. Force-angle curves for each visit were constructed using second-order polynomials. Changes in curve characteristics (optimal angle, peak force, curve height), range of motion, soreness, and creatine kinase activity were quantified. Optimal joint angle and force at optimal angle were significantly correlated from Pre1 to Pre2 (ICC = 0.821 and 0.979, respectively). Optimal angle was significantly right shifted (p = 0.035) by 10.4 ± 12.9° from Pre2 to IP and was restored by 1 day post exercise. Interestingly, the r value for curve fit was significantly decreased (p < 0.001) from Pre2 (r = 0.896) to IP (r = 0.802) and 1 day post exercise (r = 0.750). Curve height was significantly decreased (39%) IP and restored to pre-exercise height by 4 days postexercise. There was no correlation between optimal angle or curve height and other damage markers. In conclusion, force-angle relationships can be accurately described using second-order polynomials. After eccentric exercise, the force-angle curve is flattened and shifted (downward and rightward), but these changes are not correlated to other markers of muscle damage. Changes in the force-angle relationship are multifaceted, but determining the physiological significance of these changes requires further investigation.