356 research outputs found

    The Effect of Postsurgical Edema of the Knee Joint on Reflex Inhibition of the Quadriceps Femoris

    Get PDF
    Journal of Sport Rehabilitation, 1996,5,172-182 © 1996 Human Kinetics Publishers, Inc.The purpose of this case study was to investigate reflex inhibition of the quadriceps femoris in a subject with postsurgical edema of the left knee. The subject was a 45-year-old male with a traumatic knee injury with resultant edema who underwent elective arthroscopic surgery. Reflex inhibition was assessed by H-reflex elicitation in the femoral nerve and surface electromyography of the quadriceps. To assess the degree of edema, direct circumferential measurements were taken. On the first presurgical visit, the left knee demonstrated mild edema with a decrease in H-reflex amplitudes. Two days after surgery, a further reduction in amplitudes and more swelling were demonstrated followed by an increase in amplitudes and a reduction in edema on the 28th postoperative day. These findings document a relationship between reflex inhibition and joint swelling that was previously described in experimental models where joint edema was simulated

    Effects of midodrine and L-NAME on systemic and cerebral hemodynamics during cognitive activation in spinal cord injury and intact controls

    Get PDF
    This is the published version.We previously showed that increases in mean arterial pressure (MAP) following administration of midodrine hydrochloride (MH) and nitro-L-arginine methyl ester (L-NAME) resulted in increased mean cerebral blood flow velocity (MFV) during head-up tilt in hypotensive individuals with spinal cord injury (SCI) and question if this same association was evident during cognitive activation. Herein, we report MAP and MFV during two serial subtraction tasks (SSt) given before (predrug) and after (postdrug) administration of MH; (10 mg), L-NAME (1 mg/kg) or no drug (ND) in 15 subjects with SCI compared to nine able-bodied (AB) controls. Three-way factorial analysis of variance (ANOVA) models were used to determine significant main and interaction effects for group (SCI, AB), visit (MH, L-NAME, ND), and time (predrug, postdrug) for MAP and MFV during the two SSt. The three-way interaction was significant for MAP (F = 4.262; P = 0.020); both MH (30 ± 26 mmHg; P < 0.05) and L-NAME (27 ± 22 mmHg; P < 0.01) significantly increased MAP in the SCI group, but not in the AB group. There was a significant visit by time interaction for MFV suggesting an increase from predrug to postdrug following L-NAME (6 ± 8 cm/sec; P < 0.05) and MH (4 ± 7 cm/sec; P < 0.05), regardless of study group, with little change following ND (3 ± 3 cm/sec). The relationship between change in MAP and MFV was significant in the SCI group following administration of MH (r2 = 0.38; P < 0.05) and L-NAME (r2 = 0.32; P < 0.05). These antihypotensive agents, at the doses tested, raised MAP, which was associated with an increase MFV during cognitive activation in hypotensive subjects with SCI

    Isokinetic Peak Torque in Young Wrestlers

    Get PDF
    This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/detail?vid=3&sid=34ab1967-2aea-457b-b261-e90e7b05e38c%40sessionmgr11&hid=2&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=s3h&AN=20752369The purpose of the present study was to examine age-related changes in isokinetic leg flexion and extension peak torque (PT), PT/body weight (PT/ BW), and F*T/fat-free weight (PT/FFW) in young wrestlers. Male wrestlers (A^ = 108; age M ± SD = 11.3 + 1.5 years) volunteered to be measured for peak torque at 30, 180, and 300° • s'. In addition, underwater weighing was performed to determine body composition characteristics. The sample was divided into six age groups (8.1-8.9, n = 10; 9.0-9.9, n= 11; 10.0-10.9, n = 25; 11.0-11.9, n = 22; 12.0-12.9, n = 28; 13.0-13.9, n= 12), and repeated measures ANOVAs with Tukey post hoc comparisons showed increases across age for PT, PT/BW, and PT/FFW. The results of this study indicated that there were age-related increases in peak torque that could not be accounted for by changes in BW or FFW. It is possible that either an increase in muscle mass per unit of FFW, neural maturation, or both, contributes to the increase in strength across age in young male athletes

    Prevalence of Abnormal Systemic Hemodynamics in Veterans with and without Spinal Cord Injury

    Get PDF
    Advances in the clinical management of patients with acute and chronic spinal cord injury (SCI) have contributed to extended life expectancies; however longevity in those with SCI remains below that of the general population.(1) Reduced longevity in the SCI population has been attributed to increased incidence of age-associated chronic illnesses,(2) premature cardiovascular aging,(3) and increased prevalence of heart disease, stroke (4) and diabetes mellitus, (5) compared to the general population. In fact, cardiovascular disease (CVD) is now a leading cause of morbidity and mortality in the SCI population, which may be amplified due to increased risk factors such as inactivity, chronic inflammation, and impairment in autonomic cardiovascular control.(6) The American Spinal Injury Association (ASIA) impairment scale (AIS) is used to document remaining motor and sensory function following SCI; (7, 8) however, the degree of autonomic nervous system impairment is not considered within this classification schema.(9, 10) That said, impaired autonomic control of the cardiovascular system after SCI results in measurable changes in heart rate (HR) and blood pressure (BP) that loosely reflect the level and completeness of SCI documented using the AIS classification, (11, 12) but may also reflect orthostatic positioning.(6, 12, 13) The impact of these changes in HR and BP on cardiovascular health and longevity is not fully appreciated in the SCI population; however, prior to identifying the consequences of these cardiovascular abnormalities, prevalence rates of HR and BP values which fall outside the expected normal range should be documented. The International Standards to Document Autonomic Function (post-SCI) initially established guidelines for the assessment of HR and BP abnormalities in 2009, (10) which was updated in 2012, but the thresholds remained consistent. (14) Specifically, bradycardia is defined as a HR ≤ 60 beats/minute (bpm) and tachycardia as a HR ≥ 100 bpm. (14) Hypotension is defined as a systolic BP (SBP) ≤ 90 mmHg and a diastolic BP (DBP) ≤ 60 mmHg; hypertension is SBP ≥ 140 and/or DBP ≥ 90 mmHg. (14) While these definitions comply with standards established in the non-SCI population, due to decentralized cardiovascular control, they may not be appropriate for use in the SCI population. In addition, relatively recent evidence has emerged which associates adverse outcomes in the general population using other HR (15, 16) and BP (17-21) thresholds. Beyond the clinical consequences of alterations in HR and BP, persons with SCI may experience loss of independence and life quality related to the inability to adequately maintain cardiovascular homeostasis; however, until we gain a better understanding of the prevalence of these abnormalities, the development and testing of effective treatment strategies will not be a priority. Therefore, the goal of this investigation was to assess HR and BP in veterans with (SCI) and without SCI (non SCI). Similar to a recent report, (6) we hypothesized that level of SCI (i.e., the higher the lesion level the greater the prevalence of abnormal HR and BP recordings) and orthostatic positioning (i.e., increased prevalence of abnormal HR and BP recordings in the seated versus the supine position) would influence the prevalence of HR and BP abnormalities. In addition, we hypothesized that the prevalence of comorbid cardiovascular medical conditions, current smoking status, age and use of prescription anti-hypertensive (anti-HTN) medications would influence the prevalence of HR and BP abnormalities in veterans with and without SCI

    Methodological Differences in the Interpretation of Fatigue Data from Repeated Maximal Effort Knee Extensions

    Get PDF
    Background: Isokinetic fatigue protocols are commonly used in both research as well as in kinesiology education. However, fatigue quantification methods vary between studies. Objective: Therefore, the purpose of this study was to determine how fatigue quantification methods affect data interpretation and which methods may be most appropriate. Method: In this study, we quantified fatigue from a repeated maximal effort isokinetic knee extension test using different methods, as seen in published research. Nine healthy males and nine healthy females performed 50 concentric knee extensions at 180°•s-1. For each repetition, torque was quantified as either peak torque (PT), torque at the mid-point of the range of motion, and torque integrated over the full, middle 30° range of motion, and isokinetic range of motion. Fatigue Index was quantified using either the first and last three or five repetitions or the peak and last three or five repetitions. Torque slopes were quantified using all repetitions or repetitions that occurred at and beyond the repetition at which the greatest torque value occurred. Results: There was a significant inverse relationship between angle at PT and repetition number. Measures of fatigue were overestimated when torque integral over the isokinetic range of motion was utilized. When the first three or first five repetitions were utilized for Fatigue Index calculations, fatigue was underestimated. Conclusion: Results suggest that torque integral over the full range of motion is likely the best representation of strength or work. Also, researchers should omit the first few repetitions from their quantification of Fatigue Index or torque slope

    Observations from a prospective small cohort study suggest that CGRP genes contribute to acute posttraumatic headache burden after concussion

    Get PDF
    Introduction: Post-traumatic headache (PTH) is commonly reported after concussion. Calcitonin gene-related peptide (CGRP) is implicated in the pathogenesis of migraine. We explored how single nucleotide polymorphisms (SNPs) from CGRP-alpha (CALCA) and the receptor activity modifying protein-1 (RAMP1) related to headache burden during the first week after concussion. Methods: A prospective study was performed in 34 collegiate athletes who sustained a concussion. Participants completed the symptom evaluation checklist from the SCAT3 within 48 h of injury (V1), and again 4 (V2) and 7 (V3) days after injury. For each visit, the self-reported score (0–6) for headache, pressure in head, blurred vision, and sensitivity to light/noise were reported and summed to calculate the headache burden. A saliva sample was obtained and genotyped for CALCA (rs3781719) and RAMP1 (rs10185142). RAMP1 (TT, TC, CC) and CALCA (AA, AG, GG) were dichotomized (A+, A- and T+, T-, respectively), and concatenated (T+A+, T+A-, T-A+, T-A-) for analyses. Results: Headache Burden at Visit 1 was greatest in T+A+ compared to T-A+, and trended toward a significant difference with T+A-. Repeated-measures ANOVA revealed the presence of significant visit main effects (p < 0.001, η2 = 0.404), but the group (p = 0.055) and interaction effects only trended (p = 0.094). Pearson's χ2-tests revealed that 88% of those with return-to play (RTP) exclusions ≥15 days had PTH with multi-sensory symptoms (PTH+SENS) as compared to 35% in those with RTP < 14 day. Conclusion: Knowledge of RAMP1 and CALCA genotypes appear to improve an understanding the presenting features and magnitude of headache burden after concussion injury

    Corn, 1966

    Get PDF
    Cover title

    Gender Comparisons of Mechanomyographic Amplitude and Mean Power Frequency Versus Isometric Torque Relationships

    Get PDF
    This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/detail?sid=e7a03093-e666-4634-b895-d6b4313857c2%40sessionmgr13&vid=1&hid=17&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=s3h&AN=15943883This study compared the patterns of mechanomyographic (MMG) amplitude and mean power frequency vs. torque relationships in men and women during isometric muscle actions of the biceps brachii. Seven men (mean age 23.9 ± 3.5 yrs) and 8 women (mean 21.0 ± 1.3 yrs) performed submaximal to maximal isometric muscle actions of the dominant forearm flexors. Following determination of the isometric maximum voluntary contraction (MVC), they randomly performed submaximal step muscle actions in 10% increments from 10% to 90% MVC. Polynomial regression analyses indicated that the MMG amplitude vs. isometric torque relationship for the men was best fit with a cubic model (R2 = 0.983), where MMG amplitude increased slightly from 10% to 20% MVC, increased rapidly from 20% to 80% MVC, and plateaued from 80% to 100% MVC. For the women, MMG amplitude increased linearly (r2 = 0.949) from 10% to 100% MVC. Linear models also provided the best fit for the MMG mean power frequency vs. isometric torque relationship in both the men (r2 = 0.813) and women (r2 = 0.578). The results demonstrated gender differences in the MMG amplitude vs. isometric torque relationship, but similar torque-related patterns for MMG mean power frequency. These findings suggested that the plateau in MMG amplitude at high levels of isometric torque production for the biceps brachii in the men, but not the women, may have been due to greater isometric torque, muscle stiffness, and/or intramuscular fluid pressure in the men, rather than to differences in moto

    Age-Related Increases in the Shoulder Strength of High School Wrestlers

    Get PDF
    This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/detail?vid=4&sid=34ab1967-2aea-457b-b261-e90e7b05e38c%40sessionmgr11&hid=2&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=s3h&AN=20752108The purpose of this investigation was to examine age-related differences in absolute and relative isokinetic shoulder strength of high school wrestlers. A total of 122 high school wrestlers (Mage = 16.31 ± 1.18 yrs) volunteered to be measured for arm flexion and extension strength at the shoulder joint using a Cybex II dynamometer at 30, 180, and 300°-s"'. The sample was divided into four age groups: 13.75-15.00 (n=22), 15.08-16.00 (n=27). 16.08-17.00 (n=34), and 17.08-18.83 years (n=39). The results ofthis study indicated significant increases in absolute and relative arm flexion and extension strength across age when covaried for BW and FFW. In addition, comparisons with previously published data indicated differences between muscle groups in the pattern of strength gains that were dependent upon the speed of muscular contraction and may have been influenced by fiber type distribution characteristics

    Eight weeks of supplementation with a multi-ingredient weight loss product enhances body composition, reduces hip and waist girth, and increases energy levels in overweight men and women

    Get PDF
    Background: Numerous natural products are marketed and sold claiming to decrease body weight and fat, but few undergo finished product-specific research demonstrating their safety and efficacy. Objective: To determine the safety and efficacy of a multi-ingredient supplement containing primarily raspberry ketone, caffeine, capsaicin, garlic, ginger and Citrus aurantium (Prograde Metabolism™ [METABO]) as an adjunct to an eight-week weight loss program. Methods: Using a randomized, placebo-controlled, double-blind design, 70 obese but otherwise healthy subjects were randomly assigned to METABO or a placebo and underwent 8 weeks of daily supplementation, a calorie restricted diet, and exercise training. Subjects were tested for changes in body composition, serum adipocytokines (adiponectin, resistin, leptin, TNF-α, IL-6) and markers of health including heart rate and blood pressure. Results: Of the 45 subjects who completed the study, significant differences were observed in: body weight (METABO -2.0% vs. placebo -0.5%, P < 0.01), fat mass (METABO -7.8 vs. placebo -2.8%, P < 0.001), lean mass (METABO +3.4% vs. placebo +0.8%, P < 0.03), waist girth (METABO -2.0% vs. placebo -0.2%, P < 0.0007), hip girth (METABO -1.7% vs. placebo -0.4%, P < 0.003), and energy levels per anchored visual analogue scale (VAS) (METABO +29.3% vs. placebo +5.1%, P < 0.04). During the first 4 weeks, effects/trends for maintaining elevated serum leptin (P < 0.03) and decreased serum resistin (P < 0.08) in the METABO group vs. placebo were also observed. No changes in systemic hemodynamics, clinical blood chemistries, adverse events, or dietary intake were noted between groups. Conclusions: METABO administration is a safe and effective adjunct to an eight-week diet and exercise weight loss program by augmenting improvements in body composition, waist and hip girth. Adherence to the eight-week weight loss program also led to beneficial changes in body fat in placebo. Ongoing studies to confirm these results and clarify the mechanisms (i.e., biochemical and neuroendocrine mediators) by which METABO exerts the observed salutary effects are being conducted. Keywords: Dietary supplement; Raspberry ketone; Adipokine; Body composition; Fat loss; Capsaici
    • …
    corecore