Leg Extensor Power Research Articles

Long-Term Training Adaptations in Elite Male Volleyball Players

Several investigations have demonstrated differences in anthropometry, jump performance, and strength variables between developmental and elite-level volleyball players. However, within the elite level of play, the magnitude of change that can occur with training is unclear. The purpose of this investigation was to examine the anthropometric, vertical jump, and strength quality changes over 2 years in a group of national team volleyball players. Fourteen national team volleyball players (age, 23.0 ± 4.1 years; height, 1.98 ± 0.07 m; weight, 91.7 ± 7.9 kg) began and completed this study. Participants had all played international matches (representing Australia) before the examination time period and continued to do so during the international season. Anthropometry (stature, mass, and sum of 7 skinfolds), vertical jump measures (countermovement vertical jump; depth jump from 0.35 m, DJ; spike jump, SPJ, all including arm swing), and lower-body power (jump squat at body mass, and jump squat + 50% body weight, JS50) measures were tested before and at the conclusion of the investigation period. Significant (p < 0.05) improvements were observed in sum of 7 skinfolds, DJ, SPJ, and JS50 performance, with large magnitude changes (d > 0.70) in the sum of 7 skinfolds reduction, SPJ, and leg extensor power. This study has demonstrated that elite male volleyball players can improve leanness and power, which contribute to improvements in vertical jump.

Effect of different angles of knee flexion on leg extensor power in healthy individuals

ObjectivesTo investigate the effect of fixed flexion knee deformity on leg extensor power as measured by the Nottingham leg extensor power rig. DesignCross-sectional observational study. SettingOrthopaedic hospital. ParticipantsA convenience sample of 135 adult participants. Main outcome measures: leg extensor power normalised for body weight, UCLA activity scale. ResultsPower values at 0° FF were found to be significantly less than power values at 15° FF [difference 0.21W/kg SD .36], and power values at 15° FF were significantly less than those at 30° FF [difference 0.31W/kg SD .43; P<0.001) in both right and left legs. Age and activity levels were moderately negatively correlated, with UCLA score decreasing with increasing age (−0.343, P<0.0005). No significant correlation was found between activity levels measured on the UCLA and power on the LEP. ConclusionsGiven the large range of pre-operative maximal extension, the validity of testing each patient at their own maximal range of pre-intervention extension and then at the same angle post-intervention is questionable. In studies assessing change in power following an intervention, the end point angle should be standardised between individuals. In future studies investigating leg extensor power on the LEP rig pre and post intervention, it could be more appropriate to standardise the angle of FF to 30°, with individuals who are unable to achieve this position excluded from the study.

Physical performance and 10-year mortality in a 70-year-old community-dwelling population

Poor physical performance is known to be inversely related to mortality. The purpose of the present study was to determine whether an association between physical performance and 10-year mortality could be extended to a Japanese 70-year-old community-dwelling population, and to compare findings with those found in an octogenarian population. Seventy-year-old subjects residing in Niigata city, Japan, participated. Baseline examinations, including a physical performance test of four tests of muscle strength, one test of balance, and one test of agility, were carried out in June 1998 for 600 participants, and these individuals were then followed for 10 years. During the 10-year follow up, 80 subjects died. Cox regression analysis with adjustment for confounding factors showed that high scores in muscle strength tests for lower extremities, such as single-leg and double-leg extensor strength and isokinetic leg extensor power, were found to be related to decreases in total cause mortality. In an elderly 70-year-old Japanese community-dwelling population, poor muscle strength was found to be an independent predictor of total mortality. Together with our previous findings in an 80-year-old population, the association between poor strength and high mortality may have effects at 70 but not 80 years of age.

Motor and Cognitive Impairments in Parkinson Disease

Background. Balance and mobility problems are common for people with Parkinson disease (PD). Objective. To determine the relationships of motor and cognitive impairments with specific balance and mobility task performance. Methods. A total of 82 community-dwelling people with idiopathic PD were tested “on” medication. Impairments measured included leg extensor and hip abductor muscle power, freezing of gait, dyskinesia, and executive function. Balance and mobility were classified into tasks requiring anticipatory control with a change in base of support, anticipatory control without a change in support, and reactive adjustments in response to external perturbations. Associations between impairments and tasks were examined using univariable and multivariable linear regression models. Results. Univariable models revealed that muscle power was significantly related to balance and mobility, explaining 7% to 33% of the variability in task performance. Freezing of gait, dyskinesia, and executive function were not consistently related to task performance. Multivariable models that included all impairments plus disease severity, age, gender, and height explained 5% to 43% of the variability in balance and mobility tasks. Leg muscle power was the only impairment with a consistent association with performance of tasks involving anticipatory control with a change in base of support (β = 0.2 to 0.5), but the association of each muscle group was specific to individual tasks. Conclusion. Information gained from this study about the relationships between impairments and specific balance and mobility tasks may be able to guide the development of interventional strategies for people with PD.

Effects of a Salsa Dance Training on Balance and Strength Performance in Older Adults

Background: Deficits in static and particularly dynamic postural control and force production have frequently been associated with an increased risk of falling in older adults. Objective: The objectives of this study were to investigate the effects of salsa dancing on measures of static/dynamic postural control and leg extensor power in seniors. Methods: Twenty-eight healthy older adults were randomly assigned to an intervention group (INT, n = 14, age 71.6 ± 5.3 years) to conduct an 8-week progressive salsa dancing programme or a control group (CON, n = 14, age 68.9 ± 4.7 years). Static postural control was measured during one-legged stance on a balance platform and dynamic postural control was obtained while walking on an instrumented walkway. Leg extensor power was assessed during a countermovement jump on a force plate. Results: Programme compliance was excellent with participants of the INT group completing 92.5% of the dancing sessions. A tendency towards an improvement in the selected measures of static postural control was observed in the INT group as compared to the CON group. Significant group × test interactions were found for stride velocity, length and time. Post hoc analyses revealed significant increases in stride velocity and length, and concomitant decreases in stride time. However, salsa dancing did not have significant effects on various measures of gait variability and leg extensor power. Conclusion: Salsa proved to be a safe and feasible exercise programme for older adults accompanied with a high adherence rate. Age-related deficits in measures of static and particularly dynamic postural control can be mitigated by salsa dancing in older adults. High physical activity and fitness/mobility levels of our participants could be responsible for the nonsignificant findings in gait variability and leg extensor power.

Functional performance levels of strength and power needed for independence in 80-year-old individuals

Background: The ability to climb stairs (ascending and descending stair without using a handrail) and rise from a chair (rising from chairs without using an elbow rest) are among the most important measures of physical function for ADL evaluation for the independent living, and assessed by the questioners on many epidemiological studies in elderly. But little is known about the relationship between the self-reported performance level of the tasks and lower leg strength and power in very elderly people. The purpose of this study was to ascertain the relationship between the self-reported performance level of two tasks and the lower leg function in community-dwelling 80-year-old population. Methods: Out of 994 persons who were 80 years old living in Morioka City, Iwate Prefecture, Japan, 607 individuals (236 men and 371 women) underwent a physical fitness test that included measurements of leg extensor power and knee extensor strength. The ability to climb up stair and to rise from a chair was assessed by self- reported questionnaire which was ranked in three levels. The area under the receiver-operating characteristic (ROC) curve (AUC) was used to evaluate the measurements. Results: The cut-off points for the leg extensor power of subjects who could completely perform the stair-climbing and chair-rising functions were determined to be approximately 8.6 watt/kg body mass for men and 5.6 watt/kg body mass for women. In addition, the cut-off points for the knee extensor strength of subjects who could completely perform the stair-climbing and chair-rising functions were determined to be approximately 0.97 kg/kg body mass for men and 0.84 kg/kg body mass for women. Conclusions: From a practical viewpoint, the present study suggested that the cut-off points of leg extensor power and knee extensor strength can be used as targets in simple self-reported questionnaires to help in screening for mobility in 80-year-old population

Comparison of postdischarge physiotherapy versus usual care following primary total knee arthroplasty for osteoarthritis: an exploratory pilot randomized clinical trial

Objective: To evaluate a pilot trial of a postdischarge physiotherapy intervention to improve patient function versus usual physiotherapy in patients undergoing total knee arthroplasty aiming to assess: recruitment rate, feasibility and acceptability of the intervention and control, suitability of outcomes, retention and adverse events and to inform sample size calculation for a definitive trial. Design: Exploratory pilot randomized controlled trial using independent assessment. Setting: Mixed urban and rural, UK. Participants: Patients undergoing primary, elective unilateral knee arthroplasty for osteoarthritis. Intervention: Two additional home physiotherapy visits of functional weight-bearing exercises, functional task-specific training versus treatment as usual. Main outcome: Oxford Knee Score at 12 months. Secondary outcomes: completion rates, adverse events, Knee Injury and Osteoarthritis Outcome Score, leg extensor power, timed 10-m walk, timed sit-to-stand, resource use diaries. Assessments completed at baseline (pre-operatively), 3, 6 and 12 months. Results: Of 181 eligible participants 107 (59.1%) were randomized over 13 months, one participant withdrew, no adverse events. Intervention group n = 56 (mean age 67.8), control group n = 51 (mean age 70.8). The difference in mean change of Oxford Knee Scores between groups (intervention – control) at 12 months was 0.2 (95% confidence interval (CI) –3.8, 4.2), P = 0.94. Patient diaries revealed non-trial additional physiotherapy requires improved measurement. Conclusions: Successful recruitment and retention rates were achieved. The intervention appeared feasible and acceptable but may be suboptimal in intensity given recent research. A sample size of 1271 participants would be required for a fully powered randomized controlled trial using the main outcome. However new outcomes, potentially of greater validity and responsiveness, require consideration.

Factors influencing exercise performance in thoracic cancer

Patients with incurable thoracic cancer often complain of a reduced ability to exercise, but the cause of this has been little studied. Thus, we have explored how various physiological and psychological factors relate to exercise performance in this group. Inspiratory muscle strength, peripheral muscle power, lung function and mastery over breathlessness were assessed using sniff nasal inspiratory pressure, leg extensor power, simple spirometry and the mastery domain of the Chronic Respiratory Disease Questionnaire respectively. Exercise performance was assessed using the Incremental Shuttle Walking Test (ISWT) during which patients wore a K4 b(2) system permitting measurement of resting and breakpoint heart rate, minute ventilation (VE) and oxygen uptake (VO(2)). Relationships between ISWT distance and the four factors were determined using correlation and β regression coefficients. Forty-one patients (21 male, mean (SD) age 64 (8) years) walked a median [IQR] of 320 [250-430] metres and reached a mean (SD) of 76 (10), 77 (25), and 48 (14) of their percent predicted maximum heart rate, VO(2), and VE respectively. Exercise performance was significantly associated only with inspiratory muscle strength (r = 0.42, P < 0.01) and peripheral muscle power (r = 0.39, P = 0.01). These factors were also significant determinants of exercise performance (β coefficients [95%CI] 1.77 [0.53, 3.01] and 1.22 [0.31, 2.14] respectively). Of the factors examined, only inspiratory and peripheral muscle performance were significantly related to and predictive of exercise performance. Rehabilitation interventions which include inspiratory and peripheral muscle training are worth exploring further in this group of patients with thoracic cancer.

Factors associated with maximal walking speed among older community-living adults

The relative contribution of different domains on walking speed is largely unknown. This study investigated the central factors associated with maximal walking speed among older people. Cross-sectional analyses of baseline data from the SCAMOB study (ISRCTN 07330512) involving 605 community-living ambulatory adults aged 75-81 years. Maximal walking speed, leg extensor power, standing balance and body mass index were measured at the research center. Physical activity, smoking, use of alcohol, chronic diseases and depressive symptoms were self-reported by standard questionnaires. The mean maximal walking speed was 1.4 m/s (range 0.3-2.9). In linear regression analysis, age, gender and body mass index explained 11% of the variation in maximal walking speed. Adding leg extensor power and standing balance into the model increased the variation explained to 38%. Further adjusting for physical activity, smoking status and use of alcohol increased the variation explained by an additional 7%. A minor further increase in variability explained was gained by adding chronic diseases and depressive symptoms to the model. In the final model, the single most important factors associated with walking speed were leg extensor power, standing balance and physical activity, and these associations were similar in men and women and in different body mass index categories. Lower extremity impairment and physical inactivity were the central factors associated with slow walking speed among older people, probably because these factors capture the influences of health changes and other life-style factors, potentially leading to walking limitations.

Muscle power and function two years after unicompartmental knee replacement

Unicompartmental knee replacement (UKR) is a commonly performed procedure, suitable for one in four patients requiring knee replacement for end-stage osteoarthritis. Recovery and return of function is quicker than with total knee replacement (TKR), but little information is known about the recovery of muscle power. We prospectively studied a cohort of forty four patients undergoing medial UKR to document their functional recovery and leg extensor power. Muscle power was measured using a Leg Extensor Power rig preoperatively and at 1 and 2 years after surgery. Function was self reported using the Oxford Knee Score (OKS) and Tegner Activity Scale (TAS). At 1 year all patients had made significant improvements on all functional measures, with a mean gain in OKS of 15.9 and TAS of 0.84. There were also significant increases in leg extensor power (LEP) of both legs. The mean change in LEP of the operated leg at 1 year was 0.50W/kg and the non-operated leg was 0.10W/kg. Between 1 and 2 years there were very slight improvements in strength in both legs, but these were not significant. Compared with healthy age matched normative values, the UKR LEP values at 2 years after surgery were decreased. The recovery of strength and function following UKR had stabilised by 1 year and during the following year further improvements were minimal.

Factors influencing exercise capacity in people with thoracic cancer

Introduction and aimsPatients with thoracic cancer often complain of a reduced exercise capacity which can impede levels of independence and quality of life. Several factors may be responsible but there...

Is Fatigue After Stroke Associated With Physical Deconditioning? A Cross-Sectional Study in Ambulatory Stroke Survivors

Lewis SJ, Barugh AJ, Greig CA, Saunders DH, Fitzsimons C, Dinan-Young S, Young A, Mead GE. Is fatigue after stroke associated with physical deconditioning? A cross-sectional study in ambulatory stroke survivors. Objective To determine the relationship between a measure of fatigue and 2 indices of physical fitness, lower limb extensor power (LLEP) and walking economy. Design This was a cross-sectional study of patients with stroke. Fatigue was assessed by vitality (VIT) score of the Medical Outcomes Study 36-Item Short-Form Health Survey version 2 (SF-36v2). LLEP of the unaffected limb was measured using a lower leg extensor power rig. Walking economy was calculated by measuring oxygen consumption (mL·kg –1·m –1) during walking at a comfortable speed. Bivariate analyses were performed relating VIT to indices of fitness. Multiple regression analyses were also performed and included age, sex, and either SF-36v2 emotional role function or SF-36v2 mental health, as predictors of VIT. Setting Community setting. Participants Participants (N=66; 36 men; mean age ± SD, 71.0±9.9y) were all community dwelling, had survived a stroke, were able to walk independently, and had completed their stroke rehabilitation. Interventions Not applicable Main Outcome Measures The main outcome measure is SF-36v2 (VIT), with walking economy and LLEP of the limb unaffected by the stroke being independent variables. Results Walking economy was not significantly related to VIT ( R=–.024, P=.86, n=60). LLEP was positively related to VIT in bivariate analysis ( R=.38, P=.003, n=58). After controlling for age, sex, and SF-36 emotional role function (or SF-36v2 mental health if the extreme outlier was excluded), LLEP remained a significant predictor of VIT. Conclusions We found an association between fatigue and reduced LLEP. If a larger study confirms these findings, it would support the need to develop and test interventions to increase LLEP as a treatment for fatigue after stroke.

Is chair rise performance a useful measure of leg power?

Chair rise performance, which is simple to assess in a home or clinic setting, has been used as a method of predicting leg power deficit in older adults. More recently, chair rise performance has been assessed in younger populations as a baseline for assessment of subsequent age-related declines in function and power. However, as rising from a chair repeatedly not only requires lower limb strength and power but also good balance and coordination, it may not be purely a measure of leg power especially among these younger, well functioning groups who are yet to experience agerelated declines and deficits in function. The aim of this study was to assess whether chair rise performance can be considered as a predictor of leg power, and hence of deficits in this, in men and women in mid-life. We assessed the relationship of chair rise performance with leg extensor power (LEP), measured using the Nottingham Power Rig (NPR), and with standing balance performance. LEP was measured in a clinic setting in a sub-sample of 81 men and 93 women from the MRC National Survey of Health and Development, a nationally representative cohort born in Britain in 1946. The time taken to rise from a chair 10 times and standing balance time were assessed during home visits at the same age. Increasing LEP was associated with better chair rise performance among those who completed 10 chair rises in ≥15 seconds, after adjustment for body size (p=0.008). Better standing balance performance was associated with better chair rise performance in men, but not women. That LEP and standing balance are both related to chair rise time in men suggests that chair rise time should not be thought of purely as a proxy measure of leg power in middle-aged populations. This has implications for longitudinal studies which want to study age-related decline in chair rise performance.

Assessment of Leg Muscle Power Using a Low Step Height Stair Test

A stair-climbing power test using an ordinary stair is an inexpensive, practical test that is simple to perform. An individual's lower extremity power is a critical element associated with both mobility and the activities of daily living, while it is also a key determinant of independence for elderly people. However, no report has so far described the efficacy of lower height step stairs to assess the leg muscle power. PURPOSE: To determine the usefulness of the low step height stair-climbing power (LSSCP) test by comparing the results obtained from the LSSCP test with those from a leg power test in young people. METHODS: The subjects of this study included healthy young males (N=17, 20.8±2.9 yrs) and females (N=19, 20.5±2.6 yrs). The LSSCP was measured using lower height step stairs (9 cm step height, 10-stair flights, 72 cm total height). The time spent in stair climbing was measured by a contact mat connected with an electronic timer. The circuit is automatically opened at take off and closed when the subject touches the mat. The subjects were instructed to ascend the stairs as fast as they could. The stair-climbing power was then calculated with the body mass, the time spent in stair climbing, the vertical height travelled, and the gravitational acceleration. The bilateral leg extensor power (LEP) was measured using an isotonic leg power system in a sitting position. The isometric knee extension strength (KES) was measured on each side of the knee using a specially designed dynamometer. Test-test reliability was determined from participants, with the use of the intraclass correlation coefficient (ICC) model. RESULTS: The LSSCP was 338.7±48.3 watts (mean ± SD) for males and 246.1±43.0 watts for females. The LEP was 1411.7±448.7 watts (mean ± SD) for males and 718.5 ± 203.2 watts for females. The LSSCP significantly correlated with both the LEP (both p<0.05) and the KES (both p<0.05) in males and females, respectively. The ICC value of LSSCP was 0.81 for males and 0.95 for females, indicating excellent reliability. CONCLUSIONS: From a practical viewpoint as a field test, the LSSCP test was therefore found to be useful for accurately assessing the functional leg power levels.

Influence of dental occlusion on physical fitness decline in a healthy Japanese elderly population

The aim of this study was to clarify the relationship between dental occlusion and physical fitness by a longitudinal survey. A sample of 348 subjects (171 men and 177 women) aged 71 was investigated by Eichner index (EI) as an occlusal condition (Class A: no loss; Class B: partial loss; Class C: complete loss) and five types of physical fitness tests and were re-examined 8 years later. The upper 50% were sampled to analyze the correlation between each physical fitness decline and the EI at the baseline by logistic regression models. Logistic regression analyses revealed that leg extensor power (Class B vs. Class A; odds ratio = OR = 4.61, p = 0.010) and one-leg standing time with eyes open (Class C vs. Class A; OR = 4.27, p = 0.031) showed significant correlations with the EI at the baseline. In this study, partial or complete loss of occlusion was associated with a decline in leg extensor power or a decrease in one-leg standing time with eyes open. These findings suggest that maintenance of dental occlusion may prevent a decrease in activities of daily living in the elderly.

Recovery of Muscle Strength and Power After Limb-Lengthening Surgery

Barker KL, Lamb SE, Simpson HRW. Recovery of muscle strength and power after limb-lengthening surgery. Objective To report muscle strength, power, and function after limb-lengthening surgery performed by using the Ilizarov technique. Design Prospective, longitudinal observational study of a cohort of consecutive patients who underwent limb-lengthening distraction followed up for 2 years after surgery. Setting National Health Service hospital specializing in orthopedic surgery. Participants Patients (N=16) who had undergone limb-lengthening surgery performed by using the Ilizarov method (11 men, 5 women; mean age=27y; range, 13–56y). Interventions None. Main Outcome Measures Muscle strength and power were assessed by using 2 validated measures: isokinetic concentric strength of the quadriceps and hamstrings measured by using a dynamometer and leg extensor power. Measures were recorded preoperatively and at 6, 12, and 24 months after the completion of lengthening. Function was measured by 2 timed tests of functional performance: stair climbing and sit-to-stand. Results Overall results were good with high reports of function and satisfactory clinical examination. Both concentric muscle strength and leg power showed a clear pattern of decreased muscle strength at 6 months after frame removal, improving throughout the study period until it was within 3% of the preoperative value at 2 years. By 2 years, self-reported function and ability to complete timed functional tests had returned to or improved on the preoperative values. Muscle strength remained slightly below the preoperative value; this was more pronounced in the quadriceps than the hamstrings. There was no association between muscle strength and the amount of lengthening that had been undertaken. Conclusions This study suggests that there is a small residual decrease in muscle strength and power after limb-lengthening surgery but that these do not adversely impact on a patients' ability to perform everyday functional activities.

Predicting the walking speed of pedestrians on stairs

In this paper, we propose a framework in which the behaviour of a pedestrian is predicted based on the characteristics of both the pedestrian and the facility the pedestrian uses. As an example of its application, we develop a model to predict the walking speed of a pedestrian on stairs. We examine the physiology and biomechanics of walking on stairs, and then develop a model that predicts walking speed based on the weight and leg extensor power of the pedestrian, and the gradient of the stairs. The model was calibrated by experiment and validated by observations. The proposed framework establishes the importance of bridging the two types of characteristics: those of a pedestrian and those of the facility the pedestrian uses. Also, the developed walking speed model is useful for simulating how the design of stairs affects pedestrian circulation.

Raloxifene and body composition and muscle strength in postmenopausal women: a randomized, double-blind, placebo-controlled trial

To compare the effects of raloxifene and placebo on body composition and muscle strength. Randomized, double-blind, placebo-controlled trial involving 198 healthy women aged 70 years or older conducted between July 2003 and January 2008 at the University Medical Centre, Utrecht, The Netherlands. Participants were randomly assigned to receive raloxifene 60 mg or placebo daily for 12 months. Measurements were taken at baseline, 3, 6, and 12 months, and change from baseline was calculated. Main outcome measures were body composition (bioelectrical impedance analysis), muscle strength, and muscle power (maximum voluntary isometric knee extension strength, explosive leg extensor power, and handgrip strength). At 12 months, the body composition of women taking raloxifene was significantly different from that of women taking placebo: fat-free mass (FFM) had increased by a mean of 0.83 (2.4) kg in the raloxifene group versus 0.03 (1.5) kg in the placebo group (P=0.05), and total body water had increased by a mean of 0.6 (1.8) litres in the raloxifene group versus a decrease of 0.06 (1.1) litres in the placebo group (P=0.02). Muscle strength and power were not significantly different. Raloxifene significantly changed body composition (increased FFM; increased water content) compared with placebo in postmenopausal women.

337 EVALUATION OF LONG-TERM TREATMENT WITH TAPENTADOL EXTENDED RELEASE AND OXYCODONE CONTROLLED RELEASE IN PATIENTS WITH CHRONIC LOW BACK OR OSTEOARTHRITIS PAIN: RESULTS FROM PATIENT AND PHYSICIAN GLOBAL ASSESSMENTS AND THE EUROQOL 5 DIMENSION QUESTIONNAIRE

speed were obtained using the Short Physical Performance Battery (SPPB) test. Pain and physical function were measured using the WOMAC. Pearson partial correlations and linear regression analyses adjusted for age, sex, and BMI were used to examine the relationships among the variables of interest. Results: A lower percent lower extremity fat (thigh + leg) was significantly associated with reduced pain (r=0.54; p=0.02), greater physical function (r=0.66; p=0.003), and higher knee extensor strength (r=-0.58, p=0.01). No significant associations were found between percent trunk fat and these measures. Greater knee extensor strength was also significantly associated with reduced pain (r=-0.42; p=0.02) and greater physical function (r=-0.46; p=0.01). In addition, higher leg extensor power was significantly associated with faster chair rise time (r=-0.76; p=0.001) and walking speed (r=0.54; p=0.03). Conclusions: These results suggest that lower extremity fat, but not trunk fat, and weak knee extensor strength and power may play important roles in the increased pain and poor function common in older adults with knee OA. Improving knee extensor strength and reducing thigh fat may provide long-term improvements in pain and function.

336 TAPENTADOL EXTENDED RELEASE FOR THE RELIEF OF CHRONIC OSTEOARTHRITIS KNEE PAIN: RESULTS FROM THE EUROQOL-5 DIMENSION (EQ-5D) AND WESTERN ONTARIO AND MACMASTER UNIVERSITIES OSTEOARTHRITIS INDEX (WOMAC) QUESTIONNAIRES

speed were obtained using the Short Physical Performance Battery (SPPB) test. Pain and physical function were measured using the WOMAC. Pearson partial correlations and linear regression analyses adjusted for age, sex, and BMI were used to examine the relationships among the variables of interest. Results: A lower percent lower extremity fat (thigh + leg) was significantly associated with reduced pain (r=0.54; p=0.02), greater physical function (r=0.66; p=0.003), and higher knee extensor strength (r=-0.58, p=0.01). No significant associations were found between percent trunk fat and these measures. Greater knee extensor strength was also significantly associated with reduced pain (r=-0.42; p=0.02) and greater physical function (r=-0.46; p=0.01). In addition, higher leg extensor power was significantly associated with faster chair rise time (r=-0.76; p=0.001) and walking speed (r=0.54; p=0.03). Conclusions: These results suggest that lower extremity fat, but not trunk fat, and weak knee extensor strength and power may play important roles in the increased pain and poor function common in older adults with knee OA. Improving knee extensor strength and reducing thigh fat may provide long-term improvements in pain and function.