Concussion rates are commonly reported in high school and National Collegiate Athletics Association (NCAA) sports. Given that participation in collegiate recreation is on the rise, institutions should examine concussion rates within their recreational programs. We, therefore, retrospectively examined a recreational department's injury reports establishing concussion rates across (n = 16) club and (n = 10) intramural sports at a public university in the southeastern United States from 2016 to 2019. One hundred and thirty-five concussions (club n = 56; intramural n = 79) were identified and constituted 12.4% of documented injuries (n = 1,088). The intramural concussion rate was 0.57 per 1,000 athletic exposures (AEs) and AE was greatest in outdoor soccer (0.99 per 1,000 AE). Therefore, our data suggests an increased incidence of concussions in intramurals compared to published rates in NCAA and high school sports. Collegiate recreational departments should consider these concussion rates when formulating risk management strategies.

We examined the effects of acute trunk stretching on central arterial stiffness and central and peripheral blood pressure in middle-aged to older adults. Twenty-eight middle-aged to older adults (14M/14F, 72 ± 7 years, 28.5 ± 5.3 kg/m2) completed this randomized, controlled, crossover design trial. We measured carotid-femoral pulse wave velocity (cf-PWV) and central and peripheral blood pressures (BP) before and after a single bout of passively assisted trunk stretching (i.e., five rounds of six 30-s stretches) and a time-matched seated control visit (i.e., 30-min). Changes (Δ; post − pre) in cf-PWV and central and peripheral BP were compared between visits and sexes using separate linear mixed-effects models controlling for baseline values. Compared with seated control, central (systolic: − 3 ± 7 mmHg; diastolic: − 2 ± 5 mmHg) and peripheral (systolic: − 2 ± 8 mmHg; diastolic: − 1 ± 4 mmHg) BP were reduced following acute trunk stretching (ps ≤ 0.001). Between-visit differences for ∆cf-PWV (stretch: 0.09 ± 0.61 m/s; control: 0.37 ± 0.68 m/s, p = 0.038) were abolished when controlling for change in mean arterial pressure (∆MAP) (p = 0.687). The main effects of sex were detected for changes in systolic BPs (ps ≤ 0.029); more males (n = 13) saw BP reductions than females (n = 7). These findings demonstrate the superiority of acute trunk stretching over passive sitting of equated duration for BP in middle-aged to older adults, with an appreciable effect in males compared to females.

Successful hitting performance may be related to perceptual processing of visual information. The purpose of this investigation was to examine the relationship between preseason cognitive assessments, off-field preseason hitting assessment, and in-game batting performing in collegiate baseball and softball athletes. Collegiate varsity baseball (n = 10, 20.5 ± 1.0 years) and softball (n = 16, 20.3 ± 1.3 years) underwent Flanker Task and Trail Maker Tests A (TMT-A) and B (TMT-B) 24 hours prior to a pre-seasoning indoor hitting assessment. During pre-season hitting assessment, athletes selected 10 underhand pitches and were outfitted with commercially available measurement tools (i.e., HitTrax and The Blast) to quantify swing characteristics. Batting average (BA), slugging percentage (SLUG) and on-base percentage (OBP) was obtained from subsequent 14 non-conference baseball and softball games. The data from this study demonstrated a relationship between the ball's exit velocity (r = .501), bat velocity (r = .524) and average distance traveled (r = .449) during the hitting assessment and in-game BA, p < 0.05. No relationship between hitting assessment outcomes and OBP or SLUG were detected, p > 0.05. Furthermore, the Flanker-Task, TMT-A and TMT-B were not related to in game batting outcomes, p > 0.05. Therefore, these data suggest that off-season preparation should be designed to maximize swing velocity while maintaining performance (i.e., skill) of the coordinated swing.

Attentional focus strategies refer to the use of cues or other stimuli to enhance an individual’s concentration for the purpose of improving performance within a given task. PURPOSE: To examine the effects of an internal (INT), external proximal (EPr), and external distal (ED) method of attentional focus on motor unit excitation and repetitions-to-failure (RTF) during submaximal bench press performance. METHODS: Twenty-five recreationally-active males and females completed a one-repetition maximum (1RM) bench press test, followed by three days of submaximal testing at 85% 1RM to muscular failure. For each submaximal day, a specific attentional focus strategy was given by auditory cues (i.e., INT, EPr, ED) with the individual instructed to focus solely on the cue. Motor unit recruitment of the anterior deltoid, pectoralis major, and triceps brachii was measured, via electromyography (EMG), for each repetition for all interventions. RESULTS: Results indicated no differences for motor unit excitation (chest: p=0.59; triceps: p=0.50; deltoids: p=0.17) or RTF (p=0.89) among the three conditions. The INT cue, as compared to EPr and ED, elicited a ~7-10% average increase in pectoralis major motor unit excitation, despite an average of one less repetition. All effect sizes were deemed small or trivial, except for RTF between INT and ED which elicited a moderate effect size (ES=0.55). CONCLUSIONS: These findings support previous literature demonstrating increases in motor unit excitation with an internal attentional focus. However, this strategy may place a greater demand on the targeted musculature to complete a given task; thus, decreasing performance.

ABSTRACT:Kendall, BJ, Siekirk, NJ, and Lai, Q. Effects of acute high-intensity interval training on information processing speed. J Strength Cond Res 36(11): 3081-3086, 2022-This study investigated the effects of acute exercise on reaction time (RT), premotor time (i.e., central processing), and motor time (i.e., peripheral processing) using surface electromyography to fractionate RT. Fifty-eight young adults (27 men, 31 women) between the age of 18 and 40 years participated in 2 testing sessions. During visit one, subjects performed a simple RT task under regular (i.e., consistent timing) and irregular (i.e., variable timing) foreperiods. Subjects were then randomized to either an aerobic-only high-intensity interval training (HIIT) group (HIIT-A), an aerobic/resistance HIIT group (HIIT-AR), or a resting control group (CG). Both exercise groups performed a 20-minute, digital video disc-delivered HIIT exercise protocol. After exercise or rest, when controlling for cardiovascular fitness, no statistical differences were observed for the regular foreperiod conditions ( p > 0.05). For the irregular foreperiod conditions, the HIIT-A group (M = 219.8, SE = 6.5) and the HIIT-AR group (M = 218.2, SE = 5.8) had significantly faster mean RTs than the CG (M = 248.1, SE = 8.1). In addition, the HIIT-A (M = 172.1, SE = 4.6) and HIIT-AR exercise groups (M = 171.3, SE = 4.8) had significantly faster mean PMTs than the CG (M = 189.7, SE = 5.7). These findings suggest that tasks dependent on central processing may benefit from an acute bout of exercise.

BACKGROUND:School-environments are thought to be strong influences of behavioral choices. There is limited research available on the role of physical activity (PA) and school success among children with special health care needs (CSHCN). The purpose of this study was to explore differences in PA among CSHCN and non-CSHCN and how the school success index is related to PA in both groups.METHODS:Data were taken from new version of the National Survey of Children's Health (NSCH), which consolidated questions from the previous NSCH and the National Survey of Children with Special Health Care Needs (NS-CSHCN). Chi-square and logistic regression analyses were employed to examine group differences.RESULTS:There were significant differences among both subgroups, although most school-aged children did not meet recommended PA guidelines. Chi-squared analyses indicated; school engagement and the parent's perception of child safety at school were associated with the likelihood of meeting PA guidelines. Logistic regression analyses showed that the odds of meeting PA guidelines were associated with the school success index.CONCLUSIONS:Comprehensive school health programs should focus on PA both subgroups. School health educators should continue to advocate for safe and structured extracurricular activities to improve the child and adolescent's engagement and overall well-being.

Background: The epidemiology of concussion in collegiate and high school athletes has been extensively researched. Concussive injury in collegiate recreation, a less supervised sample, is limited. This preliminary study retrospectively examined the incidence and prevalence rates of concussive injuries in intramural and club sports at one institution. Methods: Injury reports were analyzed during the 2016-2019 calendar years. Concussion prevalence, incidence, and odds ratios (reported with 95% CIs) were calculated for intramural and club sports. Results: During the study period, a total of 805 injuries were reported between intramural and club sports with 111 injuries being documented as concussions. Intramural sports concussion prevalence averaged a rate of 2.77 per 1,000 unique participants while the incidence for both intramural and club sports was 13.79%. Females (2.58; 95% CI, 1.623-3.722), club lacrosse (8.923; 95% CI, 0.906-87.84), and club ultimate frisbee (7.83; 95% CI, 1.02-60.114) resulted in having higher odds of sustaining a concussion. Conclusion: Concussion prevalence and incidence was higher in this sample compared to high school and NCAA athletes. The high incidence of concussion paired with lack of medical care may result in poor outcomes in this population. Future research should replicate and expand to ensure increased rates are generalizable.

BACKGROUND: It is well established that acute exercise improves cognitive function. However, less is known about the effects of exercise on motor skill acquisition. Therefore, this study investigated the effects of acute high-intensity interval training (HIIT) on motor skill acquisition. METHODS: Sixty individuals (27 males, 33 females) between 18 and 40 years of age participated in two testing sessions separated by one week. During visit 1, participants performed one block of a continuous tracking, force control task to establish baseline ability. Participants were then randomized to either an aerobic-only HIIT group (HIT-A), an aerobic/resistance HIT group (HIIT-AR), or a resting control group. Both exercise groups performed a 20-minute, digital versatile disc (DVD)-delivered HIIT exercise protocol during visit 2. Following exercise or rest, all participants performed five blocks of the same force control task to assess skill acquisition. RESULTS: On visit 2, the HIIT-A group had a significantly lower total performance error (E) compared to the control group (P<0.05). Both exercise groups (HIIT-A and HIIT-AR) had a significantly lower peak amplitude error (PE) following exercise compared to the control group (P<0.05). No significant group differences were observed for temporal error (TE). Additionally, no significant differences were observed between the exercise groups (P>0.05). CONCLUSIONS: These findings suggest that acute HIIT-A improves motor skill acquisition compared to rest. Furthermore, improvements in acquisition appeared to be a result of improved spatial accuracy. Therefore, performing HIIT-A prior to practicing a motor task may help reduce total error during the motor skill acquisition phase.

Exercise interventions that approximate the stepping motion are thought to be useful in gait recovery after stroke. However, it remains unknown if hemiparetic asymmetry remains consistent between common exercise modes. PURPOSE: Therefore, our primary purpose was to examine contralateral mEMG (i.e., affected leg vs. non-affected leg) of chronic stroke survivors (SC) (10 ± 5 years post) and age plus sex-matched control (HC) on the NuStep Cross Trainer (NS) and Treadmill (TM). METHODS: In order to determine self-selected (SS) cadence, each participant performed a 10 minute (min) pretest on the NS and TM at an RPE between 12 and 16. After returning to resting heart rate and blood pressure, participants performed a 5-minute exercise bout on the NS and TM at the SS. The exercise order was randomized. mEMG values were recorded from the rectus femoris (RF), vastus medialis oblique (VMO), semitendinosus (ST), tibialis anterior (TA), medial gastrocnemius (MG) and soleus (SOL) bilaterally. mEMG amplitudes (uV) were converted to a percentage of isometric maximum voluntary contraction (%mvc). Five separate 2 x 2 repeated measures ANOVA were used to examine the effect of limb (i.e., affected vs. non-affected) and exercise mode (i.e., TM vs. NS) on mEMG. Post-hoc data are presented as mean and 95% confidence interval. SUMMARY OF RESULTS: SC (n = 15) and HC (n = 19) did not differ in age or BMI; p > .05. The repeated measures ANOVA found no interaction or main effects for the proximal musculature (i.e., RF, VMO, ST); p > .05. However, main effects for limb were detected for the distal musculature (i.e., MG, SOL, and TA; p < .05. The non-affected MG produced higher mEMG (M = 105.08%mvc; CI = 39.52% - 170.64%) than the affected side (M = 48.92%mvc; CI = 33.58% - 64.26%); p = .047. The non-affected SOL produced higher mEMG (M = 121.65%mvc; CI = 20.68% - 222.61%) than the affected side (M = 47.96%mvc; CI = 15.49% - 80.43%); p = .042. Post-hoc analysis revealed the non-affected TA produced higher mEMG (M = 33.29%mvc; CI = 21.76% - 44.81%) than the affected side (M = 18.79%mvc; CI = 14.30% - 23.29%); p < .001. CONCLUSION: Distal musculature demonstrated higher mEMG in the non-affected limb despite exercise mode. This gives preliminary evidence supporting the use of the NS to elicit mEMG values similar to the TM in the proximal leg musculature.

PURPOSE: The NuStep Cross Trainer (NS) approximates the bipedal and upright stepping pattern. However, it is unknown how the history of stroke may influence recumbent exercise. The purpose of this study was to examine performance outcomes on the NS in a chronic stroke condition (SC) and an age plus sex-matched control (HC). METHODS: In order to determine cadence, each participant performed a 10 minute (min) pretest on the NS at an RPE between 12 and 16. After returning to resting HR and BP, participants then performed a 5-min exercise bout on the NS. SUMMARY OF RESULTS: SC and HC did not differ in age (Mdn: 66 years vs. 57 years, respectively) or BMI (Stroke: M = 27.02 ± 4.57 vs. Healthy: M = 26.46 ± 4.63), p > .05. There were no differences in RPE, METS, elevation gain (ft), estimated energy cost (k/cal), average (avg.) speed (mph), avg. steps per min, or avg. bilateral power (W) between the HC (n = 19) and SC (n = 15); p > .05. However, HC produced higher total steps (M = 723.18 steps ± 137.64) compared to the SC (M = 597.67 steps ± 116.90); t(30) = 2.683, p = .012. Total step distance (miles) for the HC (mean rank = 19.74) was also greater than the SC (mean rank = 11.77), U = 62.0, z = -2.363, p = .018. However, ∆avg. pedal power (W) between the HC’s limbs (left-right) (M = -2.00 ± 3.528) was not different than SC (affected -non-affected) (M = -3.50 ± 4.852); t(29) = .997, p = .32. HC ΔROM (in) (mean rank = 17.50) did not differ from SC (mean rank = 13.62), U = 85.5, z = -1.214, p = .252. The SC did not demonstrate strength deficits on their affected side; p > .05. Bilateral comparison revealed the SC's affected side contributed less pedal power (18.08W ± 9.61) than the non-affected side (21.58 ± 10.34); p = .030. HC produced higher levels of force on their preferred right leg (M = 48.68lbs ± 10.05lbs vs. M = 44.42 ± 9.78); p < .001. No ROM difference was observed between limbs in HC or SC; p > .05. CONCLUSION: Healthy participants covered more distance by producing more steps (not ΔROM) in the 5-minute exercise bout on the NS. The mechanical coupling of the NS seems to encourage equal ROM contribution, but the preferred leg will contribute higher avg. power in both SC (i.e., via non-affected) and the HC (i.e., via right leg). This study was supported by a grant from the National Institutes of Health, P30 AG015281. And the Michigan Center for Urban African American Aging Research.

Objective: To investigate the impact of limb-specific fatigue on acquisition and retention of an upper extremity proprioceptive task. Methods: Twenty-two right-handed participants were randomly and equally assigned to either fatigued or non-fatigued protocols. Acquisition phase for the upper extremity task consisted of 5 blocks each with 12 trials. After 48 hours, all participants performed 1 block retention test (12 trials) with the left arm followed by 1 block transfer test (12 trials) with the right arm. Performance for each block was analyzed using a one-way analysis of variance (ANOVA). Performance differences between groups for acquisition was analyzed using a 2 x 5 (group x block) ANOVA with repeated measures on the blocks. The performance on retention-transfer was analyzed by separate ANOVAs. Statistical significance set at p<0.05.

A recumbent cross trainer (RCT) relies on similar neural networks as gait. Therefore, neurologically impaired individuals may improve walking ability after exercise on the RCT. PURPOSE: The purpose of this investigation was to compare the effects of the RCT and Treadmill (TM) on intra-exercise electromyography and post-exercise spatial-temporal gait parameters. METHODS: 34 participants were divided into two groups; stroke (CVA) (10 ± 5 years post-CVA) and age and sex-matched control. Participants completed two 5-minute exercise bouts on both the RCT and TM at an RPE based self-selected cadence. Intra-exercise Mean electromyography (mEMG) values were normalized to maximum voluntary contraction and were recorded bilaterally at the rectus femoris, vastus medialis oblique, semitendinosus, tibialis anterior, medial gastrocnemius, and soleus. Change in joint range of motion was calculated (maximum-minimum degree; ∆ROM) from wireless goniometer measures at the hip, knee, and ankle. Gait parameters were evaluated by the Wireless Gait Assessment Tool (WiGAT) immediately following each exercise bout (3 x 10m walk). HR and BP were monitored to ensure the return to pre-exercise levels. RESULTS: Stroke (n = 15) and healthy (n = 19) did not differ in age (Mdn: 66 years vs. 57 years, respectively) or BMI (Stroke: M = 27.02, SD = 4.57 vs. Healthy: M = 26.46, SD = 4.63), p > .05. Healthy participants were stronger at all joints, p < .025. Preferred TM speed was faster in the healthy condition despite no statistical difference in RPE, p < .05. RCT average steps per minute did not differ between the conditions, p >.05. RPE did not differ between groups or across exercise modes. The TM elicited a higher mEMG on a majority of the studied muscles in both populations, p <.025. TM demonstrated an increased ∆ROM in the R knee and both ankles in the healthy population, p < .025. There were no statistical differences between the TM and RCT in the CVA’s ∆ROM. WiGAT determined the RCT decreased the stance percentage (%) and increased swing % on the non-affected leg, p < .05. Neither exercise mode modulated the affected-side stance %, affected-side swing %, double support time or bilateral (affected vs. non-affected) stride length, p>.05. CONCLUSION: Five minute RCT intervention improved non-affected side gait parameters in a chronic CVA population.