A NEW EXERCISE FOR STRENGTHENING THE GLUTEUS MAXIMUS MUSCLE IN THE STANDING POSTURE

K. Aoki¹, T. Uehara², S. Yamada², R. Harashina³, T. Mizutani⁴, R. Kaneko⁵, T. Hirano¹

¹Nagoya Gakuin University, Faculty of Rehabilitation Sciences, Department of Physical Therapy, Nagoya, Japan, ²Nagoya City University West Medical Center, Department of Rehabilitation, Nagoya, Japan, ³Nagoya City Council of Social Welfare, Mizuho Ward Aged People's Welfare Center, Nagoya, Japan, ⁴The Second Narita Memorial Hospital, Department of Rehabilitation, Toyohashi, Japan, ⁵Midori Hospital, Department of Rehabilitation, Gifu, Japan

Background: Lee et al. reported that even though the senile kyphotic spine can be markedly straightened by surgery, the postoperative spine may still become stoop forward together with the pelvis due to extensive weakness of the muscles that are supposed to be engaged in supporting the spinal column. Preventing deterioration in the muscular strength of the hip extensors participating in pelvic stability is thus crucial. As exercises to improve the muscular strength of the gluteus maximus muscle (GMM), contralateral leg lift during hip bridge (HBG) and contralateral leg lift while crawling on all fours (CAF) are recommended. However, these specific positions can be difficult for elderly individuals, and problems with stability of the trunk and safety may be encountered when performing these exercises.

Purpose: We therefore devised a simple and easy new exercise in a standing position (ESP), and compared ESP with conventional strength exercises (CAF and HBG) in terms of muscular activity and utility in clinical practice.

Methods: Subjects in this study were 20 normal adults with no low back pain at baseline examination. Surface electromyographic activity (EMG) was recorded from the right side paraspinal muscles (PSM) at the L3 level, GMM, biceps femoris muscle (BFM) and gastrocnemius muscle (GCM) during 5 s of isometric contraction. Muscular activity was compared in percentage of maximal voluntary contraction (%MVC), which was amplitude of maximal voluntary contraction divided by EMG.
ESP: The subject assumed a standing position against a wall with head and back leaning against the wall. The feet are positioned slightly forward from the wall with external rotation of the hip joints and the feet touching heel to heel. ESP was performed with the subject standing on tiptoes with touching heels and both lower extremities in adduction.

Results: Comparing the three different exercises, %MVC for HBG was highest in the order of PSM, then BFM and GMM (27.3±16.6%). The %MVC for CAF was highest in the order of PSM, then GMM (32.5±22.4%). The %MVC for ESP was highest for GMM (41.1±28.2%), and lowest for PSM (20.3±16.3%).
However, no significant difference in the %MVC of GMM was evident between the three exercises. In terms of burden on the low back, ESP showed the least muscular activity of PSM among the three exercises.

Conclusions: While no significant difference in muscular activity of the GMM was seen between the three exercises, ESP tended to show the highest activity of GMM. We concluded that ESP could be applied in clinical settings. One characteristic of this exercise is that the main motions of the GMM are hip joint extension and external rotation, but if the direction of the moment arm is changed, the main motion of the GMM changes to hip joint adduction. ESP uses this effect with the change in moment arm because of the external rotation of the hip joint in a standing position.

Implications: GMM, BFM and GCM influence gait ability because they can be expected to help prevent falls and improve gait ability in ESP.

Funding acknowledgements: Research grants were received from Nagoya Gakuin University

Keywords:
Gluteus maximus muscle
Strength exercise
Prevention of kyphosis

Topics:
Musculoskeletal: spine
Musculoskeletal
Musculoskeletal: lower limb

Did this work require ethics approval? Yes

Institution: Nagoya Gakuin University

Committee: The ethics committee at Nagoya Gakuin University

Ethics number: 2015-13