Increase In Leg Strength Research Articles

EFFECTS OF TRAINING SIDE HOP OVER BARRIER WITH DUMBELL AND HEXAGON WITH DUMBELL ON LEG STRENGTH AND LEG POWER

This study was conducted at 45 students of SMAN 1 Cerme with aged between 15-16 years old. Students were divided into 3 groups. the type of research used quantitative with quasi-experimental approach. Instruments of this study were test of leg strength and leg power using Leg Dynamometer and Jump MD. The research design used matching only design. Data was anlyzed using ANOVA. The results of the research was found that training program side hop over barrier with dumbell and hexagon with dumbbell significantly increase at leg strength and leg power (Sig. 0.000 <α = 0.05). Group I, Group II and Group III had significant difference (Sig. 0.000 α = 0.005). Percentage increase in leg strength group 1 of 1,80% and leg power of 15,49%. Percentage increase in leg strength group II of 1,68% and a power of 14,27% and whereas in the control group increase in leg strength was 1.67% power at 12.32%.It can be concluded that There was an increase in leg strength and leg power in each group after the training was given. In addition, there were differences among the three groups effects seen improved in leg strength and leg power through ANOVA, where the training side hop over barrier with dumbbell and hexagon with dumbell had increased in leg strength and leg power. But side hop over barrier with dumbbell had more significant increased than hexagon with dumbbell. Key words: Side hop over with barrier dumbell, hexagon with dumbell, leg strength and leg power.

A 4-week, lifestyle-integrated, home-based exercise training programme elicits improvements in physical function and lean mass in older men and women: a pilot study.

Developing alternative exercise programmes that can alleviate certain barriers to exercise such as psychological, environmental or socio-economical barriers, but provide similar physiological benefits e.g. increases in muscle mass and strength, is of grave importance. This pilot study aimed to assess the efficacy of an unsupervised, 4-week, whole-body home-based exercise training (HBET) programme, incorporated into daily living activities, on skeletal muscle mass, power and strength. Twelve healthy older volunteers (63±3 years, 7 men: 5 women, BMI: 29±1 kg/m²) carried out the 4-week "lifestyle-integrated" HBET of 8 exercises, 3x12 repetitions each, every day. Before and after HBET, a number of physical function tests were carried out: unilateral leg extension 1-RM (one- repetition maximum), MVC (maximal voluntary contraction) leg extension, lower leg muscle power (via Nottingham Power Rig), handgrip strength and SPPBT (short physical performance battery test). A D 3-Creatine method was used for assessment of whole-body skeletal muscle mass, and ultrasound was used to measure the quadriceps cross-sectional area (CSA) and vastus lateralis muscle thickness. Four weeks HBET elicited significant (p<0.05) improvements in leg muscle power (276.7±38.5 vs. 323.4±43.4 W), maximal voluntary contraction (60°: 154.2±18.4 vs. 168.8±15.2 Nm, 90°: 152.1±10.5 vs. 159.1±11.4 Nm) and quadriceps CSA (57.5±5.4 vs. 59.0±5.3 cm 2), with a trend for an increase in leg strength (1-RM: 45.7±5.9 vs. 49.6±6.0 kg, P=0.08). This was despite there being no significant differences in whole-body skeletal muscle mass, as assessed via D 3-Creatine. This study demonstrates that increases in multiple aspects of muscle function can be achieved in older adults with just 4-weeks of "lifestyle-integrated" HBET, with a cost-effective means. This training mode may prove to be a beneficial alternative for maintaining and/or improving muscle mass and function in older adults.

A 4-week, lifestyle-integrated, home-based exercise training programme elicits improvements in physical function and lean mass in older men and women: a pilot study

Background: Developing alternative exercise programmes that can alleviate certain barriers to exercise such as psychological, environmental or socio-economical barriers, but provide similar physiological benefits e.g. increases in muscle mass and strength, is of grave importance. This pilot study aimed to assess the efficacy of an unsupervised, 4-week, whole-body home-based exercise training (HBET) programme, incorporated into daily living activities, on skeletal muscle mass, power and strength. Methods: Twelve healthy older volunteers (63±3 years, 7 men: 5 women, BMI: 29±1 kg/m²) carried out the 4-week “lifestyle-integrated” HBET of 8 exercises, 3x12 repetitions each, every day. Before and after HBET, a number of physical function tests were carried out: unilateral leg extension 1-RM (one- repetition maximum), MVC (maximal voluntary contraction) leg extension, lower leg muscle power (via Nottingham Power Rig), handgrip strength and SPPBT (short physical performance battery test). A D 3-Creatine method was used for assessment of whole-body skeletal muscle mass, and ultrasound was used to measure the quadriceps cross-sectional area (CSA) and vastus lateralis muscle thickness. Results: Four weeks HBET elicited significant (p<0.05) improvements in leg muscle power (276.7±38.5 vs. 323.4±43.4 W), maximal voluntary contraction (60°: 154.2±18.4 vs. 168.8±15.2 Nm, 90°: 152.1±10.5 vs. 159.1±11.4 Nm) and quadriceps CSA (57.5±5.4 vs. 59.0±5.3 cm 2), with a trend for an increase in leg strength (1-RM: 45.7±5.9 vs. 49.6±6.0 kg, P=0.08). This was despite there being no significant differences in whole-body skeletal muscle mass, as assessed via D 3-Creatine. Conclusions: This study demonstrates that increases in multiple aspects of muscle function can be achieved in older adults with just 4-weeks of “lifestyle-integrated” HBET, with a cost-effective means. This training mode may prove to be a beneficial alternative for maintaining and/or improving muscle mass and function in older adults.

A 4-week, lifestyle-integrated, home-based exercise training programme elicits improvements in physical function and lean mass in older men and women: a pilot study

Developing alternative exercise programmes that can alleviate certain barriers to exercise such as psychological, environmental or socio-economical barriers, but provide similar physiological benefits e.g. increases in muscle mass and strength, is of grave importance. This pilot study aimed to assess the efficacy of an unsupervised, 4-week, whole-body home-based exercise training (HBET) programme, incorporated into daily living activities, on skeletal muscle mass, power and strength. Twelve healthy older volunteers (63±3 years, 7 men: 5 women, BMI: 29±1 kg/m²) carried out the 4-week "lifestyle-integrated" HBET of 8 exercises, 3x12 repetitions each, every day. Before and after HBET, a number of physical function tests were carried out: unilateral leg extension 1-RM (one- repetition maximum), MVC (maximal voluntary contraction) leg extension, lower leg muscle power (via Nottingham Power Rig), handgrip strength and SPPBT (short physical performance battery test). A D 3-Creatine method was used for assessment of whole-body skeletal muscle mass, and ultrasound was used to measure the quadriceps cross-sectional area (CSA) and vastus lateralis muscle thickness. Four weeks HBET elicited significant (p<0.05) improvements in leg muscle power (276.7±38.5 vs. 323.4±43.4 W), maximal voluntary contraction (60°: 154.2±18.4 vs. 168.8±15.2 Nm, 90°: 152.1±10.5 vs. 159.1±11.4 Nm) and quadriceps CSA (57.5±5.4 vs. 59.0±5.3 cm 2), with a trend for an increase in leg strength (1-RM: 45.7±5.9 vs. 49.6±6.0 kg, P=0.08). This was despite there being no significant differences in whole-body skeletal muscle mass, as assessed via D 3-Creatine. This study demonstrates that increases in multiple aspects of muscle function can be achieved in older adults with just 4-weeks of "lifestyle-integrated" HBET, with a cost-effective means. This training mode may prove to be a beneficial alternative for maintaining and/or improving muscle mass and function in older adults.

Wii-Based and Supervised Exercise Training Decrease Falls Risk in Older Adults with Type 2 Diabetes

Loss of balance resulting in falls is a serious health issue for older persons with type 2 diabetes (T2D). One intervention shown to produce benefits for these individuals is various types of exercise training. However, motivation is commonly cited as a barrier to consistent physical activity participation in unsupervised conditions. Interactive video games, such as the Nintendo Wii system, have been viewed as an innovative tool for engaging individuals in activity at home. PURPOSE: To assess the differences between supervised and unsupervised (using the Nintendo Wii) exercise training aimed at improving balance, reaction time, lower limb strength, and falls risk in older adults with T2D. METHODS: 47 older adults with T2D participated in 12 weeks of training: 32 (mean age 67.7 + 5 yr) completed supervised training (ST) while 15 (mean age 66.3 + 5 yr) completed unsupervised Wii training. ST sessions (40 min each, 3 times a week) consisted of lower limb stretches followed by leg, abdominal, and lower back exercises. The Wii training group completed three 40-min sessions on the Wii balance board per week. The Wii-based exercises were self-selected to emphasize balance and postural control. Prior to and following training, assessments of lower limb strength (i.e., isometric knee extension and flexion), falls risk (using the Physiological Profile Assessment), balance, postural coordination, vision, proprioception and reaction time were performed. RESULTS: Following training, participants in both the ST and Wii groups showed a significant decline in overall falls risk (ST, 0.59 + 0.12 to 0.22 + 0.14; Wii, 0.33 + 0.13 to 0.17 + 0.11; p < 0.05). Falls risk reductions were driven by significant improvements in knee extension (ST, 31.5 kg to 36.4 kg; Wii, 31.1 to 34.3 kg), knee flexion (ST, 16.9 to 19.3 kg; Wii, 17.0 to 18.3 kg), faster reaction times (ST, 278 to 247 ms; Wii, 244 to 225 ms) and improved postural coordination (ST, 13.4 to 9.1 errors; Wii, 9.7 to 6.5 errors). CONCLUSION: Both ST and unsupervised Wii exercise training interventions led to a reduction in falls risk in older adults with T2D, accompanied by increases in leg strength, faster reaction times, and improved balance coordination. Thus, both supervised and unsupervised exercise may lead to improvements in falls risk in older adults with T2D.

Increase in leg strength after outpatient cardiac rehabilitation contributes to improvement of gait speed in patients aged 75 years or older with cardiovascular disease

Increase in leg strength after outpatient cardiac rehabilitation contributes to improvement of gait speed in patients aged 75 years or older with cardiovascular disease

A Combined and Intensive Exercise Model Improves Physical Capacity in Cardiac Patients

Objective: We have measured the effect of combined strength and high intensity endurance training on physical capacity and lipid profile in patients with heart and coronary diseases. We wanted to see whether cardiac patients were able to increase training intensity to improve strength without losing endurance capacity. Methods: Thirty heart-operated subjects participated in an intervention period of 10 weeks. The age of the participants was between 52-72 years. The Resistance-Interval group (RE-INT) practiced four times a week with two intensive endurance (spinning) sessions and two strength training sessions. The endurance training consisted of intervals where the heart rate reached>90% of maximum heart rate. Strength training was performed in three series with a load of 8-12 repetition maximum (RM). The subjects in the control group (CON) performed two to three sessions per week according to a national program specialized for coronary patients (called “Ullevaal model”). We had a randomized controlled trial. Results: Maximal leg strength increased in both groups during the intervention, but the increase was higher in the RE-INT group (from 107.9 ± 8.1 kg to 162.0 ± 8.4 kg) compared to the CON group (from 110.8 ± 8.9 to 125.4 ± 9.5 ) (p<0.001). Strength in chest press, the maximal oxygen uptake and the concentration of high densitylipoprotein (HDL) protein increased in both groups during the test period. However, no differences were observed between the RE-INT and CON group. Low density-lipoprotein (LDL), blood pressure and body weight did not change during the intervention period in any of the groups. Conclusion: cardiac patients were able to increase training intensity, strength and maximal oxygen uptake during a period of 10 weeks. We found that combined training has an effective impact on the increase in leg strength. The increase in muscle strength can be vital for the everyday quality of life in cardiac patients.

New strategies for exercise training in osteoporosis

In the prevention and treatment of osteoporosis, movement with muscle strengthening and proprioceptive training plays a major role. This was taken into consideration in the guidelines by the governing body on osteoporosis (Dachverband Osteoporose, DVO) from 2014 on prophylaxis, diagnosis and treatment of osteoporosis and in the DVO guidelines from 2008 on physiotherapy and exercise therapy for osteoporosis. Increases in lumbar bone density of between 0.5 % and 2.5 % can be achieved in women by strengthening exercises with high resistance. With this combination and strengthening of the quadriceps muscle a reduction of falls and hence the fracture risk could also be achieved. In traumatology, training for muscle strengthening is not always possible, especially for elderly patients. Practically relevant alternatives are regular walking and aquatraining, which may also lead to a significant increase in bone mineral density. Furthermore, large effects can be achieved with alternating side whole-body vibration (WBV) training with whole body vibration plates with only 3 days of training per week and with short training periods (15-20min). Rates of increase in leg strength between 20 % and almost 40 % and in bone density between 0.5 % and 4 % in 6 months have been described. Whether and with what intensity whole body vibration therapy could be used for e.g. more rapid healing of fractures, is currently unclear. Initial positive results have been described in animal models.

Deconstructing the power resistance relationship for squats: A joint-level analysis.

Generating high leg power outputs is important for executing rapid movements. Squats are commonly used to increase leg strength and power. Therefore, it is useful to understand factors affecting power output in squatting. We aimed to deconstruct the mechanisms behind why power is maximized at certain resistances in squatting. Ten male rowers (age = 20 ± 2.2 years; height = 1.82 ± 0.03 m; mass = 86 ± 11 kg) performed maximal power squats with resistances ranging from body weight to 80% of their one repetition maximum (1RM). Three-dimensional kinematics was combined with ground reaction force (GRF) data in an inverse dynamics analysis to calculate leg joint moments and powers. System center of mass (COM) velocity and power were computed from GRF data. COM power was maximized across a range of resistances from 40% to 60% 1RM. This range was identified because a trade-off in hip and knee joint powers existed across this range, with maximal knee joint power occurring at 40% 1RM and maximal hip joint power at 60% 1RM. A non-linear system force-velocity relationship was observed that dictated large reductions in COM power below 20% 1RM and above 60% 1RM. These reductions were due to constraints on the control of the movement.

Relationships Between Changes In Performance And Body Composition Variables After A Ten-week Resistance Training Intervention

Changes in body composition variables as well as strength and power performance are both apparent after resistance training interventions. PURPOSE: To compare multiple body composition variables and how they relate to changes in strength and power. METHODS: Eighteen trained men (25.8 ± 4.3y; 176.7 ± 5.0cm; 80.4 ± 12.0kg) completed a 10 week resistance training program. The first 8 weeks consisted of daily undulating periodized resistance training 3 days per week, focusing on either muscular hypertrophy, power, or strength. The final 2 weeks featured an overreach and taper phase. Tests consisted of 1RM strength of the bench press and leg press, a 30s Wingate, bench press peak power and velocity, and vertical jump height, peak power, and peak velocity. Body composition variables include total body and segmental Dual-Energy X-Ray Analysis (DXA), multi-frequency bioelectrical impedance (MFBIA), Single Frequency BIA (SFBIA), Bioimpedance Spectroscopy (BIS), Skinfold thicknesses, limb circumferences, and diagnostic ultrasound (US). RESULTS: With the exception of Wingate variables (p > 0.09), significant increases in strength and power were observed for all performance measurements (p < 0.01). Significant positive relationships were observed for MFBIA fat mass (FM) and MFBIA percent fat (%Fat) (r > 0.50, p < 0.03) for bench press velocity as well as for DXA trunk lean mass and leg press 1RM (r = 0.576, p = 0.012). Significant negative relationships were discovered for skinfold thicknesses of the suprailliac and vertical jump height (r = -0.507, p = 0.032) as well as US fat thickness and leg press 1RM (r = -0.711, p = 0.001). CONCLUSION: Changes in body composition variables (FM, FFM, %Fat, etc.) measured by different methods appear to produce varying relationships with performance variables after resistance training. An increase in fat measured by MFBIA appears to be associated with an increase in bench press velocity and an increase in trunk lean mass measured by DXA may predict an increase in leg strength. Also, a loss in subcutaneous hip (Skinfold) and thigh (US) fat may increase both vertical jump height and lower body strength, respectively. Thus, relationships between changes in body composition and performance after a resistance exercise intervention are dependent on both the method used as well as the variables being analyzed.

Loaded Whole-Body Vibration Training Decreases Arterial Stiffness and Wave Reflection in Overweight/Obese Young Women

Obese sedentary individuals exhibit arterial dysfunction, as observed by increased pulse-wave velocity (PWV) and augmentation index ([email protected]), markers of arterial stiffness and pulse wave reflection, respectively. Since obesity and muscle strength are inversely related, muscle weakness in young obese women can be counteracted by high intensity resistance training. However, adverse effects on arterial function have been observed in young individuals following this exercise modality. Unloaded whole-body vibration training (U-WBVT) has improved PWV and [email protected] in overweight/obese pre- and post-menopausal women. However, U-WBVT appears to be low-intensity and the effects of moderate-intensity WBVT on arterial function and leg muscle strength are currently unknown. PURPOSE: To evaluate whether loaded whole-body vibration training (L-WBVT) would result in greater improvements in femoral-ankle PWV (faPWV, leg) and brachial-ankle PWV (baPWV, systemic), [email protected], and leg muscle strength when compared to U-WBVT and a non-exercising control (CON). METHODS: Twenty-two young overweight/obese women (age 20 ± 1 y; BMI 30.9 ± 0.7 kg/m2) were randomized into a CON, U-WBVT, or L-WBVT for 6 weeks. FaPWV, baPWV, [email protected], and leg muscle strength (1RM) were assessed at baseline and following 6 weeks. RESULTS: Significant reductions in faPWV (-0.41± 0.10 m/s; P < 0.01), baPWV (-0.55 ± 0.20 m/s; P < 0.05), and [email protected] (-4.9 ± 2.1 %; P < 0.05) were observed after L-WBVT; however, only the decreases in faPWV and [email protected] were significant (P < 0.01) compared with the CON group. Both U-WBVT and L-WBVT increased leg strength compared to CON (P < 0.01). CONCLUSIONS: L-WBVT significantly reduced leg arterial stiffness and wave reflection. The decrease in baPWV was mainly due to the reduction in faPWV. Although both WBVT protocols increased leg muscle strength similarly, L-WBVT may be a more efficient intervention than U-WBVT to improve arterial function in young obese women.

Knee Extension and Flexion Strength in Recreational Surfers

A trend for increased leg strength in the leg positioned in the back compared to front of the surfboard has been reported previously in a study with limited sample size. This preliminary data suggests that an asymmetry may exist in surfer’s leg strength and that this may be influenced by surfer’s stance on the surfboard. PURPOSE: The purpose of this investigation was to test the hypothesis that leg strength in surfers, as assessed by isokinetic knee extension and flexion at contraction velocities ranging from 60-300deg/sec, would be greater in the leg positioned in the back compared to front of the surfboard. METHODS: Forty-four recreational surfers (5 female, 39 male) with a mean age of 41.0±2.1yrs participated in this study. Leg dominance was assessed in all subjects using a ball kicking task prior to measurements of strength. Single leg isokinetic knee extension and flexion strength was measured in both legs using an isokinetic dynamometer (Biodex, System 3). Following a five-minute warmup on a cycle ergometer (Monark), subjects performed five repetitions of maximal knee extension and flexion at contraction velocities of 60, 120, 180, 240, and 300deg/sec. A thirty-second recovery period was provided between each contraction velocity. RESULTS: All subjects reported surfing to be their primary form of physical activity with 8.8±0.8hrs/wk and had 23.9±2.2yrs of surfing experience. There were no significant differences in torques between legs for knee extension (60deg/sec: 141.4±5.3 vs. 150.1±5.9, 120deg/sec: 107.2±4.2 vs. 109.8±4.7, 180deg/sec: 84.4±3.8 vs. 87.2±3.7, 240deg/sec: 71.7±3.5 vs. 72.2±3.6, 300deg/sec: 61.2±3.4 vs. 63.0±3.5ft-lbs) and flexion (60deg/sec: 86.8±3.5 vs. 87.2±3.4, 120deg/sec: 72.1±2.9 vs. 72.3±2.7, 180deg/sec: 62.1±2.6 vs. 62.3±2.5, 240deg/sec: 56.3±2.6 vs. 56.5±2.4, 300deg/sec: 49.0±2.4 vs. 49.2±2.5ft-lbs) across all contraction velocities. CONCLUSIONS: Contradictory to previously reported data, the current results suggest that recreational surfers’ leg strength is not influenced by surfing stance.

Impact of l-citrulline supplementation and whole-body vibration training on arterial stiffness and leg muscle function in obese postmenopausal women with high blood pressure

Aging is associated with increased arterial stiffness (pulse wave velocity, PWV) and muscle strength/mass loss. Exercise training alone is not always effective to improve PWV and lean mass (LM) in older women. To investigate the independent and combined effects of whole-body vibration training (WBVT) and l-citrulline supplementation on PWV and muscle function in women, forty-one postmenopausal women aged 58±3years and body mass index (34±2kg/m2) were randomly assigned to the following groups: WBVT, l-citrulline, and WBVT+l-citrulline for 8weeks. WBVT consisted of four leg exercises three times weekly. Aortic (cfPWV) and leg (faPWV) PWV, leg LM index, leg strength, and body fat percentage (BF%) were measured before and after the interventions. WBVT+l-citrulline decreased cfPWV (−0.91±0.21m/s, P<0.01) compared to both groups. All interventions decreased faPWV (P<0.05) similarly. Leg LM index increased (2.7±0.5%, P<0.001) after WBVT+l-citrulline compared with l-citrulline. Both WBVT interventions increased leg strength (~37%, P<0.001) compared to l-citrulline while decreased BF% (~2.0%, P<0.01). Reductions in cfPWV were correlated with increases in leg LM index (r=−0.63, P<0.05). Our findings suggest that leg muscle strength and arterial stiffness can be improved after WBVT, but its combination with l-citrulline supplementation enhanced benefits on aortic stiffness and leg LM. Therefore, WBVT+l-citrulline could be an intervention for improving arterial stiffness and leg muscle function in obese postmenopausal women with prehypertension or hypertension, thereby reducing their cardiovascular and disability risk.

Anterior Cruciate Ligament Reconstruction With Contralateral Autogenous Patellar Tendon Graft

Background: Few surgeons use a contralateral patellar tendon autograft for primary anterior cruciate ligament (ACL) reconstruction because of concern for donor site morbidity. Hypothesis: There will be no difference in quadriceps muscle strength or International Knee Documentation Committee (IKDC) subjective scores in patients with contralateral grafts compared with patients with ipsilateral grafts. Study Design: Cohort study; Level of evidence, 3. Methods: Between 2007 and 2009, a total of 279 patients who underwent primary ACL reconstruction with autogenous patellar tendon graft from the contralateral knee met the inclusion criteria of unilateral knee involvement, no arthritic changes preoperatively, and minimum 2-year follow-up objective and subjective evaluations. A control group was obtained of 58 patients who had the same inclusion criteria and were of the same age but who underwent surgery with ipsilateral graft. Patients underwent a goal-directed and sequential postoperative rehabilitation program that first emphasized controlling a hemarthrosis and obtaining full knee range of motion immediately after surgery, followed by increasing leg strength and performing functional activities. The rehabilitation for the contralateral donor site emphasized high-repetition/low-resistance exercises beginning the day after surgery. The IKDC subjective data were compared between surgery groups. Quadriceps muscle strength was evaluated in both knees compared with the preoperative values obtained in the noninvolved knee and between knees at 2 years postoperatively. Results: Quadriceps muscle strength compared with the preoperative normal value (mean ± SD) was 105% ± 29% in the ipsilateral ACL-reconstructed knee versus 114% ± 28.4% in the contralateral donor knee (P < .01) and 116% ± 25% in the contralateral ACL-reconstructed knee (P = .0339). Mean side-to-side strength (ACL-reconstructed knee/opposite knee) was 98.4% ± 13.6% in the contralateral group versus 92.9% ± 13.0% in the ipsilateral group (P < .01). The mean total IKDC score was 92.4 ± 9.6 for the contralateral donor knee. The mean IKDC total score for the ACL-reconstructed knee was 88.8 ± 12.3 in the contralateral group and 88.9 ± 11.2 in the ipsilateral group (P = .626). Conclusion: After ACL reconstruction with contralateral patellar tendon graft, patients can achieve strength symmetry between legs after surgery without experiencing adverse subjective symptoms after graft harvest. Furthermore, strength return can be superior with a contralateral graft than with an ipsilateral graft.

A behavioral mechanism of how increases in leg strength improve old adults' gait speed.

We examined a behavioral mechanism of how increases in leg strength improve healthy old adults’ gait speed. Leg press strength training improved maximal leg press load 40% (p = 0.001) and isometric strength in 5 group of leg muscles 32% (p = 0.001) in a randomly allocated intervention group of healthy old adults (age 74, n = 15) but not in no-exercise control group (age 74, n = 8). Gait speed increased similarly in the training (9.9%) and control (8.6%) groups (time main effect, p = 0.001). However, in the training group only, in line with the concept of biomechanical plasticity of aging gait, hip extensors and ankle plantarflexors became the only significant predictors of self-selected and maximal gait speed. The study provides the first behavioral evidence regarding a mechanism of how increases in leg strength improve healthy old adults’ gait speed.

Donor-Site Recovery after Anterior Cruciate Ligament Reconstruction with Contralateral Autogenous Patellar-Tendon Graft

Objectives:To evaluate the recovery of the donor site after ACL-reconstruction with a contralateral autogenous patellar tendon graft as compared with an ipsilateral graft. Specifically, we compared the International Knee Documentation Committee (IKDC) subjective scores between groups and compared to established normative data. Furthermore we evaluated quadriceps muscle strength between surgery groups.Methods:Between 2007 and 2009, 279 patients who underwent primary ACL reconstruction with an autogenous patellar tendon graft from the contralateral knee met the inclusion criteria of unilateral knee involvement, no evidence of arthritic changes preoperatively, and minimum 2 year follow-up objective and subjective evaluations. A control group was obtained of 58 patients who had the same inclusion criteria, were of the same age, but underwent surgery with ipsilateral graft. Patients underwent a goal-directed and sequential postoperative rehabilitation program that emphasized controlling a hemarthrosis, obtaining full knee range of motion as soon as possible after surgery, increasing leg strength, and functional activities to return patients back to sports. The rehabilitation for the contralateral donor site emphasized high repetition/low resistance exercises beginning the day after surgery to reconstitute the patellar tendon size and strength. IKDC subjective data was compared between surgery groups and established normative data. Quadriceps muscle strength was evaluated in both knees compared to the pre-operative values obtained in the non-involved knee; strength between knees at 2 years postoperatively was also evaluated.Results:When comparing quadriceps muscle strength to its pre-operative baseline value, the ipsilateral control group that had statistically significantly less strength in the ACL-reconstructed knee at 105% ± 29% compared with the contralateral group that had 114% ± 28.4% strength in the donor knee (P < .01) and 116% ± 25% strength in the ACL-reconstructed knee (P = .0339). When side-to-side strength was evaluated at 2 years post-operatively, the contralateral group had 98.4% ± 13.6% quadriceps muscle strength compared with 92.9% ± 13.0% in the ipsilateral control group (P < .01). The mean total IKDC scores obtained at the 2-year follow-up was 92.4 ± 9.6 for contralateral donor-knee, 88.8 ± 12.3 in the contralateral ACL-reconstructed knee, and 88.9 ± 11.2 for the control group ACL-reconstructed knee (p=0.960). There was also no statistical significant differences between groups for any of the IKDC sub-scores or total score (All P-values >.136; Table 1). The mean IKDC scores compared with established normative data of noninjured people of the same age and sex showed no large effect size differences between groups.Conclusion:With proper rehabilitation after surgery, use of a contralateral bone-patellar tendon-bone autograft with ACL reconstruction does not cause unresolved donor-site strength loss or subjective symptoms.

Sensitivity of sensor-based sit-to-stand peak power to the effects of training leg strength, leg power and balance in older adults

Increasing leg strength, leg power and overall balance can improve mobility and reduce fall risk. Sensor-based assessment of peak power during the sit-to-stand (STS) transfer may be useful for detecting changes in mobility and fall risk. Therefore, this study investigated whether sensor-based STS peak power and related measures are sensitive to the effects of increasing leg strength, leg power and overall balance in older adults. A further aim was to compare sensitivity between sensor-based STS measures and standard clinical measures of leg strength, leg power, balance, mobility and fall risk, following an exercise-based intervention. To achieve these aims, 26 older adults (age: 70–84 years) participated in an eight-week exercise program aimed at improving leg strength, leg power and balance. Before and after the intervention, performance on normal and fast STS transfers was evaluated with a hybrid motion sensor worn on the hip. In addition, standard clinical tests (isometric quadriceps strength, Timed Up and Go test, Berg Balance Scale) were performed. Standard clinical tests as well as sensor-based measures of peak power, maximal velocity and duration of normal and fast STS showed significant improvements. Sensor-based measurement of peak power, maximal velocity and duration of normal STS demonstrated a higher sensitivity (absolute standardized response mean (SRM): ≥0.69) to the effects of training leg strength, leg power and balance than standard clinical measures (absolute SRM: ≤0.61). Therefore, the presented sensor-based method appears to be useful for detecting changes in mobility and fall risk.

Effects of Aqua Aerobic Therapy Exercise for Older Adults on Muscular Strength, Agility and Balance to Prevent Falling during Gait

[Purpose] The purpose of the present study was to examine the effects of an aqua aerobic therapy exercise for older adults on biomechanical and physiological factors affecting gait. [Subjects] A total of 15 subjects participated in this study and they were randomly divided into the experimental and the control group. [Methods] Physiological variables, leg strength, power and flexibility, and biomechanical variables, both kinematic and kinetic, were measured before and after the aqua aerobic therapy exercise. Each subject was instructed to walk along an elevated walkway and during the trials a trapdoor opened at random to create a 10 cm falling perturbation. Full body motion and kinetics was gathered during the gait. [Results] There were significant reductions in body weight, and body fat mass, and stride time after the perturbation. Significant increases in leg strength corresponded to the maximum joint moment of the landing leg showing that the subjects' ability for recovery of balance after the perturbation improved. [Conclusion] As the results showed significant improvements in gait pattern and recovery time after perturbed gait, we conclude that aqua aerobic therapy is an effective exercise method for training older adults to reduce their risk of falling.

Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited into a 12-week cycling program. The same pre- and postmeasures as used in Study 1 were collected. Results. Study 1: participants who had cycled in the last month performed significantly better on measures of decision time and response time. Study 2: cycling at least one hour a week was associated with significant improvements in balance (decision time and response time) and timed single leg standing. Conclusions. Cycling by healthy older adults appears promising for improving risk factors for falls.

Early Poststroke Rehabilitation Using a Robotic Tilt-Table Stepper and Functional Electrical Stimulation

Background. Stroke frequently leaves survivors with hemiparesis. To prevent persistent deficits, rehabilitation may be more effective if started early. Early training is often limited because of orthostatic reactions. Tilt-table stepping robots and functional electrical stimulation (FES) may prevent these reactions. Objective. This controlled convenience sample study compares safety and feasibility of robotic tilt-table training plus FES (ROBO-FES) and robotic tilt-table training (ROBO) against tilt-table training alone (control). A preliminary assessment of efficacy is performed. Methods. Hemiparetic ischemic stroke survivors (age 58.3 ± 1.2 years, 4.6 ± 1.2 days after stroke) were assigned to 30 days of ROBO-FES (n = 38), ROBO (n = 35), or control (n = 31) in addition to conventional physical therapy. Impedance cardiography and transcranial doppler sonography were performed before, during, and after training. Hemiparesis was assessed using the British Medical Research Council (MRC) strength scale. Results. No serious adverse events occurred; 8 patients in the tilt-table group prematurely quit the study because of orthostatic reactions. Blood pressure and CBFV dipped <10% during robot training. In 52% of controls mean arterial pressure decreased by ≥20%. ROBO-FES increased leg strength by 1.97 ± 0.88 points, ROBO by 1.50 ± 0.85 more than control (1.03 ± 0.61, P < 0.05). CBFV increased in both robotic groups more than in controls (P < 0.05). Conclusions. Robotic tilt-table exercise with or without FES is safe and may be more effective in improving leg strength and cerebral blood flow than tilt table alone.