Effect of Assistance Timing in Knee Extensor Muscle Activation During Sit-to-Stand Using a Bilateral Robotic Knee Exoskeleton

Hikers and soldiers usually walk up and down slopes with a load carriage, causing injuries of the musculoskeletal system, especially during a prolonged load journey. The slope walking has been reported to lead to higher leg extensor muscle activities and joint moments. However, most of the studies investigated muscle activities or joint moments during slope walking without load carriage or only investigated the joint moment changes and muscle activities with load carriages during level walking. Whether the muscle activation such as the signal amplitude is influenced by the mixed factor of loads and grades and whether the influence of the degrees of loads and grades on different muscles are equal have not yet been investigated. To explore the effects of backpack loads on leg muscle activation during slope walking, ten young male participants walked at 1.11 m/s on a treadmill with different backpack loads (load masses: 0, 10, 20, and 30 kg) during slope walking (grade: 0, 3, 5, and 10°). Leg muscles, including the gluteus maximus (GM), rectus femoris (RF), hamstrings (HA), anterior tibialis (AT), and medial gastrocnemius (GA), were recorded during walking. The hip, knee, and ankle extensor muscle activations increased during the slope walking, and the hip muscles increased most among hip, knee, and ankle muscles (GM and HA increased by 46% to 207% and 110% to 226%, respectively, during walking steeper than 10° across all load masses (GM: p = 1.32 × 10−8 and HA: p = 2.33 × 10−16)). Muscle activation increased pronouncedly with loads, and the knee extensor muscles increased greater than the hip and ankle muscles (RF increased by 104% to 172% with a load mass greater than 30 kg across all grades (RF: p = 8.86 × 10−7)). The results in our study imply that the hip and knee muscles play an important role during slope walking with loads. The hip and knee extension movements during slope walking should be considerably assisted to lower the muscle activations, which will be useful for designing assistant devices, such as exoskeleton robots, to enhance hikers’ and soldiers’ walking abilities.

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Sit-to-stand Test to Evaluate Knee Extensor Muscle Size and Strength in the Elderly: A Novel Approach

Journal of PHYSIOLOGICAL ANTHROPOLOGY ◽

10.2114/jpa2.28.123 ◽

2009 ◽

Vol 28 (3) ◽

pp. 123-128 ◽

Cited By ~ 63

Author(s):

Yohei Takai ◽

Megumi Ohta ◽

Ryota Akagi ◽

Hiroaki Kanehisa ◽

Yasuo Kawakami ◽

...

Keyword(s):

Knee Extensor ◽

The Elderly ◽

Extensor Muscle ◽

Muscle Size ◽

Stand Test ◽

Sit To Stand ◽

Novel Approach

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P.1.14 Knee extensor muscle force correlates with and may predict sit to stand ability in congenital muscular dystrophy

Neuromuscular Disorders ◽

10.1016/j.nmd.2013.06.398 ◽

2013 ◽

Vol 23 (9-10) ◽

pp. 745-746

Author(s):

M. Jain ◽

D. Hall ◽

M. Waite ◽

J. Collins ◽

K. Meilleur ◽

...

Keyword(s):

Muscular Dystrophy ◽

Muscle Force ◽

Congenital Muscular Dystrophy ◽

Knee Extensor ◽

Extensor Muscle ◽

Sit To Stand

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Clinical Measures Predicting Knee Extensor Muscle Activation During a Maximal Voluntary Isometric Contraction

Journal of Exercise Sports & Orthopedics ◽

10.15226/2374-6904/2/4/00138 ◽

2015 ◽

Vol 2 (4) ◽

pp. 1-10

Author(s):

Gordon L Warren

Keyword(s):

Isometric Contraction ◽

Muscle Activation ◽

Knee Extensor ◽

Extensor Muscle ◽

Maximal Voluntary Isometric Contraction ◽

Clinical Measures

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Efficacy of cardiac rehabilitation with motion assistance from wearable cyborg hybrid assistive limb in patients with chronic heart failure: a randomized controlled trial

European Heart Journal ◽

10.1093/ehjci/ehaa946.1067 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

H Watanabe ◽

A Koike ◽

H Kato ◽

L Wu ◽

K Hayashi ◽

...

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Cardiac Rehabilitation ◽

Exercise Therapy ◽

Knee Extensor ◽

Control Group ◽

Cardiac Events ◽

Rehabilitation Programs ◽

Sit To Stand ◽

Knee Extensor Strength

Abstract Background Recent Cochrane Systematic Review suggested that the participation in cardiac rehabilitation is associated with approximately 20% lower cardiovascular mortality and morbidity. Exercise therapy is the key component of cardiac rehabilitation programs. In recent years, innovative technologies have been introduced into the field of rehabilitation, and a typical example is the wearable cyborg Hybrid Assistive Limb (HAL). The wearable cyborg HAL provides motion assistance based on detection of bioelectrical signals on the skin surface when muscle forces are generated. The lumbar-type HAL is expected to expand the therapeutic options for severe cardiac patients who have difficulty in performing usual cardiac rehabilitation programs, such as bicycle pedaling or walking. Purpose We aim to compare the efficacy of exercise therapy performed with motion assistance from a lumbar-type HAL versus conventional training (sit-to-stand exercise without HAL) in patients with chronic heart failure. Methods This clinical trial is a randomized, non-blinded, and controlled study. Twenty-eight heart failure patients (73.1±13.8 years) who have difficulty in walking at the usual walking speed of healthy subjects were randomly assigned to 2 groups (HAL group or control group) with a 1:1 allocation ratio and performed sit-to stand exercise either with HAL or without HAL for 5 to 30 minutes once a day, and 6 to 10 days during the study period. The brain natriuretic peptide (BNP), isometric knee extensor strength, standing ability (30-seconds chair-stand test: CS-30), short physical performance battery (SPPB) and 6-minute walking distance (6MWD) were measured before and after the completion of cardiac rehabilitation. Cardiac events such as death, re-hospitalization, myocardial infarction and worsening of angina pectoris and heart failure during 1 year after discharge were evaluated. Results There was no significant difference in the number of days of exercise therapy between the two groups. BNP, SPPB and 6MWD were improved in both groups. In the HAL group, the isometric knee extensor strength (0.29±0.11 vs 0.35±0.11 kgf/kg, p=0.003) significantly improved and CS-30 (5.5±5.1 vs 8.2±5.3, p=0.054) tended to improve. However, in the control group, either the isometric knee extensor strength (0.35±0.11 vs 0.36±0.14 kgf/kg, p=0.424) or CS-30 (6.0±4.3 vs 9.2±6.2, p=0.075) did not significantly change. HAL group showed significantly more improvement in the isometric knee extensor strength than control group (p=0.045). Cardiac events occurred in 20% in the HAL group and 43% in the control group. Conclusion The improvement in isometric knee extensor strength with the assistance from lumbar-type HAL suggests that exercise therapy using this device may be useful in chronic heart failure patients with flail or sarcopenia, a strong poor prognostic factor in these patients. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (JSPS KAKENHI grant number JP17K09485) and funded by the ImPACT Program of the Council for Science, Technology and Innovation (Cabinet Office, Government of Japan) (grant number 2017-PM05-03-01).

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Effects of different initial foot positions on kinematics, muscle activation patterns, and postural control during a sit-to-stand in younger and older adults

Journal of Biomechanics ◽

10.1016/j.jbiomech.2021.110251 ◽

2021 ◽

Vol 117 ◽

pp. 110251

Author(s):

Woohyoung Jeon ◽

Hao-Yuan Hsiao ◽

Lisa Griffin

Keyword(s):

Older Adults ◽

Postural Control ◽

Muscle Activation ◽

Activation Patterns ◽

Muscle Activation Patterns ◽

Sit To Stand

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Kinetics, kinematics, and knee muscle activation during sit to stand transition in unilateral and bilateral knee osteoarthritis

Gait & Posture ◽

10.1016/j.gaitpost.2021.02.023 ◽

2021 ◽

Vol 86 ◽

pp. 38-44

Author(s):

Marina Petrella ◽

Luiz Fernando A. Selistre ◽

Paula R.M.S. Serrão ◽

Giovanna C. Lessi ◽

Glaucia H. Gonçalves ◽

...

Keyword(s):

Knee Osteoarthritis ◽

Muscle Activation ◽

Bilateral Knee ◽

Sit To Stand ◽

Knee Muscle

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Initial phase of maximal voluntary and electrically stimulated knee extension torque development at different knee angles

Journal of Applied Physiology ◽

10.1152/japplphysiol.00230.2004 ◽

2004 ◽

Vol 97 (5) ◽

pp. 1693-1701 ◽

Cited By ~ 118

Author(s):

C. J. de Ruiter ◽

R. D. Kooistra ◽

M. I. Paalman ◽

A. de Haan

Keyword(s):

Muscle Activation ◽

Knee Extensor ◽

Surface Emg ◽

Knee Extension ◽

Voluntary Contraction ◽

Voluntary Activation ◽

Knee Angle ◽

Time Integral ◽

Voluntary Contractions ◽

Torque Development

We investigated the capacity for torque development and muscle activation at the onset of fast voluntary isometric knee extensions at 30, 60, and 90° knee angle. Experiments were performed in subjects ( n = 7) who had high levels (>90%) of activation at the plateau of maximal voluntary contractions. During maximal electrical nerve stimulation (8 pulses at 300 Hz), the maximal rate of torque development (MRTD) and torque time integral over the first 40 ms (TTI40) changed in proportion with torque at the different knee angles (highest values at 60°). At each knee angle, voluntary MRTD and stimulated MRTD were similar ( P < 0.05), but time to voluntary MRTD was significantly longer. Voluntary TTI40 was independent ( P > 0.05) of knee angle and on average (all subjects and angles) only 40% of stimulated TTI40. However, among subjects, the averaged (across knee angles) values ranged from 10.3 ± 3.1 to 83.3 ± 3.2% and were positively related ( r2 = 0.75, P < 0.05) to the knee-extensor surface EMG at the start of torque development. It was concluded that, although all subjects had high levels of voluntary activation at the plateau of maximal voluntary contraction, among subjects and independent of knee angle, the capacity for fast muscle activation varied substantially. Moreover, in all subjects, torque developed considerably faster during maximal electrical stimulation than during maximal voluntary effort. At different knee angles, stimulated MRTD and TTI40 changed in proportion with stimulated torque, but voluntary MRTD and TTI40 changed less than maximal voluntary torque.

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