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Accurate determinations of individuals' one-repetition maximum (1RM) are critical when evaluating the effectiveness of an exercise intervention involving progressive resistance training (RT). Traditional ("bottom-up"; BT) testing methods involve progressions from low to maximal loads and are commonly used in clinical and laboratory environments. Concerns about the reliability of BT testing in certain populations suggest a different technique may be more effective.

Background: Although claims of increased injury rates with Thursday night National Football League (NFL) games exist, a paucity of data exist substantiating these claims. Purpose: To evaluate the effect of rest between games on in-game injury rates as it pertains to overall injury incidence, location, and player position. Study Design: Descriptive epidemiologic study. Methods: Data were obtained from official NFL game books for regular season games from all 32 teams for the 2013-2016 seasons. All in-game injuries recorded in official game books were included. Rest periods between games were classified as short (4 days), regular (6-8 days), or long (≥10 days). Overall observed injury rates per team-game were analyzed in relation to different rest periods using negative binomial regression. For results with significant overall findings, pairwise comparisons were tested using the Wald chi-square test. Exploratory secondary analyses were performed in a similar fashion to assess differences in injury rates for the different rest periods when stratified by anatomic location and player position. Results: A total of 2846 injuries were identified throughout the 4 seasons. There was an overall significant difference in injuries per team-game between short, regular, and long rest ( P = .01). With short rest, an observed mean of 1.26 injuries per game (95% CI, 1.06-1.49) was significantly different from the 1.53 observed injuries per game with regular rest (95% CI, 1.46-1.60; P = .03), but not compared with the 1.34 observed injuries per game with long rest ( P = .56). For player position, only the tight end, linebacker, and fullback group demonstrated significant differences between the injury rates for different rest categories. Quarterback was the only position with more injuries during games played on Thursday compared with both regular and long rest. This specific analysis was underpowered and the difference was not significant ( P = .08). No differences were found regarding injury rates in correlation with differences in rest periods with different injury locations. Conclusion: A short rest period between games is not associated with increased rates of observed injuries reported in NFL game books; rather, our data suggest there are significantly fewer injuries for Thursday night games compared with games played on regular rest. Future research correlating rest and quarterback injury rates is warranted.

The presence of postganglionic sympathetic denervation is well established in Parkinson’s disease (PD). Denervation at cardiac and blood vessel sites may lead to abnormal cardiovascular and hemodynamic responses to exercise. The aim of the present investigation was to examine how heart rate (HR) and hemodynamics are affected by an exercise test in PD patients without orthostatic hypotension. Thirty individuals without orthostatic hypotension, 14 individuals with PD, and 16 age-matched healthy controls performed an exercise test on a cycle ergometer. Heart rate, blood pressure, and other hemodynamic variables were measured in a fasted state during supine rest, active standing, exercise, and supine recovery. Peak HR and percent of age-predicted maximum HR (HRmax) achieved were significantly blunted in PD (p < 0.05, p < 0.01). HR remained significantly elevated in PD during recovery compared with controls (p = 0.03, p < 0.05). Systolic, diastolic, and mean arterial pressures were significantly lower at multiple time-points during active standing in PD compared with controls. Systemic vascular resistance index (SVRI) decreased significantly at the onset of exercise in PD, and remained significantly lower during exercise and the first minute of supine recovery. End diastolic volume index (EDVI) was significantly lower in PD during supine rest and recovery. Our results indicate for the first time that normal hemodynamics are disrupted during orthostatic stress and exercise in PD. Despite significant differences in EDVI at rest and during recovery, and SVRI during exercise, cardiac index was unaffected. Our finding of significantly blunted HRmax and HR recovery in PD patients has substantial implications for exercise prescription and recovery guidelines.

Background Periodization is a systematic training calendar designed to provide variations in performance targeting, while maximizing results and reducing the potential for overtraining. When provided across multiple weeks, termed a mesocycle, it may also incorporate active recovery periods using specified drills designed to translate neuromuscular gains into targeted functional abilities. There are a number of models that can be used when applying periodization to resistance training (RT). Among the most common are the linear (LP) and daily fixed non-linear (NLP) models. It is currently unknown whether an optimal periodization strategy exists that will maximize benefits for older adults; therefore, we compared the impact of these two periodization models on neuromuscular and functional measures in a group of older persons living independently in the community. Methods Thirty-six older adults, 58–80 years of age, were randomly assigned to either a LP (n = 16; 69.3 ± 4.6 y) or NLP (n = 14; 68.9 ± 6.7 y) group. The LP group performed 12 weeks of training comprised of separate 4-week strength and power training cycles, each followed by a 2-week recovery period incorporating translational exercises. The NLP group performed the strength, power, and translational training on three separate days during the week. Neuromuscular testing included seated chest press and leg press strength and power tests, while physical function testing included the gallon jug shelf test, laundry transfer test, floor stand-up, chair-to-stand test, and 8 foot timed up-and-go. Results 3 (time) × 2 (sex) × 2 (group) repeated measures ANOVA revealed both periodization strategies were equally effective at inducing neuromuscular and functional improvements and that men generally produced more strength and power than women. Conclusions Both LP and NLP can be used to improve strength, power, and functional performance in healthy untrained older adults when strength, power and functional training cycles are involved. Therefore, personal preference and variety should be considered when deciding which approach to use, provided high-speed power and translational recovery components are included.

To our knowledge, no prior study has evaluated outcomes after elective lumbar spinal surgery in human immunodeficiency virus (HIV) patients without acquired immunodeficiency syndrome (AIDS). This review investigated the impact of HIV-positive status (without AIDS) on outcomes after elective lumbar fusion for degenerative disc disease (DDD).Adult patients registered in the Nationwide Inpatient Sample (2002-2011) undergoing elective lumbar fusion for DDD were extracted. Multivariable regression techniques were used to explore the association of HIV positivity with outcomes after lumbar fusion.This cohort included 612,000 hospitalizations (0.07% were HIV positive) of lumbar fusion for DDD. Compared with HIV-negative patients undergoing lumbar fusion, HIV-positive patients were younger (47 vs. 55 years), male (61% vs. 42%), largely insured by Medicare (30% vs. 5%), and had higher rates of chronic obstructive pulmonary disease (23.7% vs. 14.6%) (all P0.001) but had lower rates of obesity, hypertension, and diabetes (all P0.001). Multivariable models demonstrated HIV positivity to be associated with higher odds for an adverse event (odds ratio [OR], 1.92; P0.001), in-hospital mortality (OR, 39.91; P 0.001), wound complications (OR, 2.60; P = 0.004), respiratory (OR, 5.43; P0.001) and neurologic (OR, 1.96; P = 0.039) complications, and higher costs (7.1% higher; P = 0.011) compared with non-HIV patients. There were no differences in thromboembolic events, cardiac or gastrointestinal complications, discharge disposition, or length of stay.Even in this selected cohort of well-controlled HIV patients, there were high complications, with concerning rates of death and respiratory complications. These data shed new light on elective spine surgery in HIV patients and may influence the treatment algorithm of surgeons who are familiar with older papers.

Background:Quadriceps tendon (QT) autografts are increasingly popular for anterior cruciate ligament reconstruction (ACLR). However, no study has compared QT autografts with bone–patellar tendon–bone (BTB) autografts regarding the electromechanical delay (EMD), the peak torque (PT), and the rate of force development (RFD) in the superficial quadriceps muscles (rectus femoris [RF], vastus medialis [VM], and vastus lateralis [VL]).Hypotheses:We hypothesized (1) there would be a significantly lower PT, lower RFD, and longer quadriceps EMD of the operative limb for the QT versus the BTB autograft; (2) the PT, the RFD, and the quadriceps EMD of the operative limb would be significantly depressed compared with those of the nonoperative limb, regardless of the surgical technique; and (3) there would be greater increases in the RF EMD than in the VM or the VL EMD.Study Design:Cohort study; Level of evidence, 3.Methods:A total of 34 patients (age, 18-40 years), who had undergone ACLR (QT, n = 17; BTB, n = 17) at least 1 year before testing and performed 3 perceived maximal effort isometric tests, which were time synchronized with surface electromyography (EMG) on their operative and nonoperative limbs, were included in this study. EMD, PT, and RFD data were analyzed using a 2 (limb) × 2 (graft) × 3 (repetition) mixed repeated-measures analysis of variance.Results:The EMD, the PT, and the RFD were not significantly affected by graft choice. For the VL, a significant repetition × graft × limb interaction was detected for the VL EMD ( P = .027; ηp = 0.075), with repetition 3 having longer EMD than repetition 2 (mean difference [MD], 16 milliseconds; P = .039). For the RF EMD, there was a significant repetition × limb interaction ( P = .027; ηp = 0.074), with repetition 3 being significantly longer on the operative versus the nonoperative limb (MD, 24 milliseconds; P = .004). Further, the operative limb EMD was significantly longer for repetition 3 versus repetition 2 (MD, 17 milliseconds; P = .042). For the PT, there was a significant effect for repetition ( P = .003; ηp = 0.114), with repetition 1 being significantly higher than both repetitions 2 (MD, 8.52 N·m; P = .001) and 3 (MD, 7.79 N·m; P = .031). For the RFD, significant limb ( P = .034; ηp = 0.092) and repetition ( P = .010; ηp = 0.093) effects were seen, with the nonoperative limb being significantly faster than the operative limb (MD, 23.7 N·m/s; P = .034) and repetition 1 being significantly slower than repetitions 2 (MD, -20.46 N·m/s; P = .039) or 3 (MD, −29.85 N·m/s; P = .002).Conclusion:The EMD, the PT, and the RFD were not significantly affected by graft type when comparing QT and BTB autografts for ACLR; however, all neuromuscular variables were affected regardless of the QT or the BTB harvest.

Progressive resistance training (RT) is one of the most effective interventions for reducing age-related deficits in muscle mass and functional capacity.To compare four approaches to load progressions in RT for older adults to determine if an optimal method exists.Eighty-two healthy community-dwelling older adults (71.8 ± 6.2 yr) performed 11 wk of structured RT (2.5 d·wk) in treatment groups differing only by the method used to increase training loads. These included percent one repetition maximum (%1RM): standardized loads based on a percentage of the one repetition maximum (1RM); rating of perceived exertion (RPE): loads increased when perceived difficulty falls below 8/10 on the OMNI-Resistance Exercise Scale perceived exertion scale; repetition maximum (RM): loads increased when a target number of repetitions can be completed with a given load; repetitions in reserve (RiR): identical to RM except subjects must always maintain ≥1 "repetition in reserve," thus avoiding the possibility of training to temporary muscular failure.Multiple analyses of covariance indicated no significant between-group differences on any strength (chest press 1RM; leg press 1RM) or functional performance outcome (usual walking speed, maximum walking speed, 8-ft timed up-and-go, gallon jug transfer test, 30 s sit-to-stand). The RPE group found the exercise to be significantly more tolerable and enjoyable than subjects in the RiR, RM, and %1RM groups.Given the RM, RPE, %1RM, and RiR methods appear equally effective at improving muscular strength and functional performance in an older population, we conclude that the RPE method is optimal because it is likely to be perceived as the most tolerable and enjoyable, which are two important factors determining older adults' continued participation in RT.

Guidelines for improving maximal concentric strength through resistance training (RT) have traditionally included large muscle-group exercises, full ranges of motion, and a load approximating 85% of the 1-repetition maximum (1RM). Supramaximal eccentric training (SME; controlled lowering of loads above the concentric 1RM) has also been shown to be effective at increasing concentric 1RM in the lower body, but concerns regarding injury risk, postexercise soreness, and null benefit over traditional methods (TRAD) may limit the practical utility of this approach.The purpose of this study was to determine whether SME elicits greater lower-body strength improvements than TRAD.Key inclusion criteria were regular exercise modalities typical of nonspecialized exercise facilities (e.g., leg press; key exclusion: isokinetic dynamometer) and at least 6 weeks of RT exposure, leading to 5 studies included in the current meta-analysis. Unbiased effect-size measures that quantify the mean difference in lower-body 1RM between SME and TRAD were extracted.Supramaximal eccentric training did not appear to be more effective than TRAD at increasing lower-body 1RM ([Formula: see text] = .33, SE = .26, z = 1.26, 95% CI [-0.20, 0.79], p = .20, IThe selection of SME over TRAD in RT programs designed to increase lower-body 1RM does not appear warranted in all populations. Further research should clarify the merit of periodic SME in TRAD-dominant RT programs as well as whether a differential effect exists in trained individuals.

Background Declines in strength and power are cardinal symptoms of Parkinson's disease (PD), a progressive neuromuscular disorder. Progressive resistance training (PRT) has been shown to reduce a wide variety of PD-related motor deficits; however, no study has examined differences between the two most common RT methodologies utilized in this population, high-load, low velocity strength training (ST) and low-load, high-velocity power training (PT). The primary purpose of this study was to compare the effects of ST and PT on measures of strength, power, balance and functional movement in persons with PD. Method Thirty-five persons with mild to moderate PD (Hoehm and Yahr Stages = 1–3; UPDRS Part III = 30.6 ± 14.0) were randomized into either a ST or PT group involving 12 weeks of supervised PRT (2 visits per week). Leg press (LP) and chest press (CP) muscular strength (1RM) and muscular peak power (PP) were assessed before and after the twelve week training period as primary outcome measures. In addition, secondary measures of balance (Berg Balance Assessment (BBA), dynamic posturography (DMA), Modified Falls Efficacy Scale (MFES)), functional movement (timed up-and-go), and quality of life (PDQ-39 summary index and Mobility subscore) were obtained at the same time points, given the impact of PD symptoms on fall probability and independence. Results Repeated measures ANCOVA revealed significant improvements in LP 1RM (Mdiff = 54.89 kg, 95% CI: 43.38, 66.40; p Conclusions Both ST and PT appear to be effective at reducing the neuromuscular deficits associated with PD; however, the use of these interventions for improving functional performance was not supported.

Objectives: The objective of this study was to evaluate the impact rest time between games may have on injury rates as it pertains to overall incidence, injury location and player position. Methods: For this descriptive epidemiological study, data was obtained from official NFL gamebooks. In-game injuries were queried for all regular season games from all 32 teams over the course of four seasons (2013 to 2016). Only injuries which resulted in a stoppage of time during gameplay were included. Player position and injured body part were taken from the following week’s injury report. Rest periods between games were classified as short (4 days), regular (6-8 days), or long (10+ days) rest. Positions were categorized into Quarterback, Skill (wide receiver, running back and defensive backs), Lineman, and Other (fullback, linebacker and tightend). Overall observed injury rates, as well as injury rates specific to anatomic location and player position, were analyzed in correlation to different rest periods. Statistical significance was determined using the ANOVAprocedure of observed mean injuries per game. Pairwise analysis, through 2 sample T-test, was conducted to assess statistical significance between short, regular and long rest. Results: A total of 2,846 injuries were identified throughout the four seasons. ANOVA testing of all 3 cohorts taken together demonstrated a statistically significant difference between injuries/game between short, regular, and long rest (p = 0.012). With short rest, a mean of 1.26 injuries/game were observed (95% CI 1.046, 1.470), which was statistically significantly different when compared to the 1.53 observed injuries/game with regular rest (95% CI 1.463, 1.601; p = 0.029). Games with short rest were not found to be significantly different when compared to the 1.34 observed injuries/game associated with long rest (95% CI 1.186, 1.486; p = 0.555). Regarding player positions, only the Other cohort achieved statistically significantly less observed injuries/game with games played on Thursday compared to regular (p=0.0002) and long (p = 0.026). The quarterback position was the only position which sustained more injuries than expected with games played on Thursday compared to both regular and long rest; however, these results did not reach statistical significance (p = 0.09). No statistical difference was found regarding injury location in correlation to differences in rest periods. Conclusion: Our data suggests that there is a significant association between the amount of rest between games and observed injuries in the NFL. Interestingly, Thursday night games were found to have fewer injuries per game when compared to games played on regular rest. Subgroup analysis revealed fewer observed injuries with short rest for linebackers, fullbacks, and tightends. Although quarterbacks were observed to have more injuries than expected on short rest, this did not reach statistical significance. The results of this study do not support that less rest associated with Thursday night games leads to higher injury rates; however, quarterback injury rates may potentially be impacted with shortened rest. [Table: see text]