Muscle strength decline is associated with normal aging and may be accelerated by illness, disease, or injury. Decreased physical activity resulting from COVID-19 mitigation efforts is exacerbating the incidence of muscle disuse atrophy in older adults. Strength declines may lead to functional and mobility deficits with increased risk of falls, injury, or death. According to the CDC, each year three million adults are treated in emergency departments for injuries related to falls. By 2030 fall deaths are anticipated to rise to seven per hour. Accurate assessment of strength using validated tests and objective measures is crucial to creating an appropriate treatment plan and achieving outcomes that reduce fall risk.
Assessing strength with objective tests and measures:
Overall Strength:
• Medical Research Council Sum Score (MRC-SS): Measures strength bilaterally for the shoulder abductors, elbow flexors, wrist extensors, hip flexors, and foot dorsiflexors. MMT strength grades (0-5) bilaterally for the six muscle groups are added; maximum score is 60. (Vanpee et al., 2014)
Upper Extremity Strength:
• Dynamometer: Grip strength is assessed using a handheld dynamometer with the individual seated, shoulder adducted, elbow to 90º, forearm in neutral, and wrist between 0-15º ulnar deviation. (Shirley Ryan, 2020)
• Arm Curl Test: 30-second timed test with the individual sitting upright in an armless chair. The individual performs arm curls with weights (5# for women and 8# for men) and the number of repetitions are counted and compared to norms. (Rikli and Jones, 2013)
Lower Extremity Strength:
• 30-second Sit-to-Stand: Number of full sit to stand repetitions performed in 30 seconds. (Rikli & Jones, 2013)
• 5x Sit-to Stand: Individual performs five repetitions of sit to stand as quickly as possible. (Shirley Ryan, 2020)
Research related to strength improvements:
• An intervention using balance exercises or elastic resistance exercise is effective at improving the muscle strength and balance of old-old elderly. (Cho et al., 2014)
• Patterned electrical neuromuscular stimulation (PENS) applied to the quadriceps and hamstrings muscles of patients with COPD resulted in 30% increased strength and 34% increased walking distance. (Bourjeily et al., 2002)
• Electrical stimulation, similar to physical exercise, attenuates the functional decline associated with aging, improving muscle strength and mass, maintaining overall size of muscle fibers (decreasing during aging), activating satellite cells, and guaranteeing muscle adaptation. (Kern et al, 2014)
Upper Extremity Strength Treatments (progressive resistance exercise (PRE), PENS, cycling with or without e-stim, and MFAC) provided within the context of a comprehensive clinical treatment pathway may assist in the improvement of strength and function.
Lower Extremity Strength Treatments (PRE, PENS, cycling with or without e-stim, and MFAC) provided within the context of a comprehensive clinical treatment pathway may assist in the improvement of strength and function.
References:
Bourjeily-Habr, G., Rochester, C. L., Palermo, F., Snyder, P., & Mohsenin, V. (2002). Randomized controlled trial of transcutaneous electrical nerve stimulation of the lower extremities in patients with chronic obstructive pulmonary disease. Thorax, 57(2), 1045-1049.
Centers for Disease Control and Prevention (CDC). (n.d.) STEADI – Older Adult Fall Prevention. Retrieved September 18, 2020, https://www.cdc.gov/steadi
Cho, S. I., & An, D. H. (2014). Effects of a Fall Prevention Exercise Program on Muscle Strength and Balance of the Old-old Elderly. Journal of Physical Therapy Science. https://doi.org/10.1589/jpts.26.1771
Kern, H., Barberi, L., Löfler, S., Sbardella, S., Burggraf, S., Fruhamann, H., Carraro, U., Mosole, S., Sarabon, N., Vogelauer, M., Mayer, W., Krenn, M., Cvecka, J., Romanello, V., Pietrangelo, L., Protasi, F., Sandri, M., Zampieri, S., & Musaro, A., (2014). Electrical Stimulation counteracts muscle decline in seniors. Frontiers in Aging Neuroscience. 189(6),1-11.
Rikli, R. E., & Jones C. J. (2013). Senior Fitness Test Manual. Champaign, IL: Human Kinetics.
Shirley Ryan Ability Lab. (n.d.) Rehabilitation Measures Database. Retrieved September 18, 2018, https://www.sralab.org/rehabilitation-measures
Vanpee, G., Hermans, G., Segers, J., & Gosselink, R. (2014). Assessment of limb muscle strength in critically ill patients: a systematic review. Critical Care Medicine. https://doi.org/10.1097/CCM.0000000000000030
