Research Output

Muscle activity during aquatic and land exercises in people with and without low back pain.

Chronic low back pain (CLBP) is the most prevalent musculoskeletal disorder. Aquatic exercises are commonly used by physical therapists for CLBP treatment and management; however, there are no data on trunk muscle activation during aquatic exercises in people with CLBP.
We quantified activation of trunk and gluteal muscles, exercise intensity, pain, and perceived exertion in people with and without CLBP when performing water and land exercises.
The study used a cross-sectional design.
Twenty participants with non-specific CLBP and 20 healthy participants performed 15 aquatic exercises and 15 similar land exercises. Mean and peak muscle activation were measured bilaterally from erector spinae, multifidus, gluteus maximus, gluteus medius, rectus abdominis, external oblique, and internal oblique, using waterproof and wireless surface electromyography. Exercise intensity (heart rate), perceived exertion (Borg scale), and for the CLBP group, pain (visual analog scale) were recorded.
There were no significant between-group differences. Significant between-environment differences were found in heart rate (always higher on land), exertion (higher in the water for 3 exercises and on land for 6 exercises) and muscle activation (higher on land in 29% and in the water in 5% of comparisons). Pain levels were low, but pain was reported more than twice as frequently on land than in water (7.7% vs 3.7%, respectively).
People with high levels of disability and CLBP classification were not included.
People with mild-to-moderate CLBP had similar exercise responses to healthy controls. Aquatic exercise produced sufficient muscle activation, intensity, and exertion, and should not be assumed to be less strenuous or less effective in activating trunk and pelvic muscles than exercise on land. These data can be used to inform design and prescription of rehabilitation programs and interventions.

  • Type:


  • Date:

    23 January 2019

  • Publication Status:


  • Publisher

    Oxford University Press (OUP)

  • DOI:


  • ISSN:


  • Library of Congress:

    RC1200 Sports Medicine

  • Dewey Decimal Classification:

    613 Personal health & safety

  • Funders:

    Chief Scientists Office


Psycharakis, S. G., Coleman, S. G. S., Linton, L., Kaliarntas, K., & Valentin, S. (2019). Muscle activity during aquatic and land exercises in people with and without low back pain. Physical Therapy, 99(3), 297-310.



Electromyography, Physiotherapy, Rehabilitation, Water, Hydrotherapy, Musculoskeletal, Biomechanics,

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    Muscle Activity During Aquatic and Land Exercises in People With and Without Low Back Pain


    © 2019 American Physical Therapy Association
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