Associate Director for Translational Sciences, Center for Research on Aging
VAMC 10 N. Greene Street
Education and Training
BA University of Arizona, Tucson, AZ (Sociology/Biology)
MS Pennsylvania State Univerisity, State College, PA (Exercise Physiology)
PhD University of Maryland, College Park, MD (Exercise Physiology)
Post-doctoral Fellow University of Maryland, School of Medicine, Baltimore MD (Gerontology and Metabolism)
A main focus of my research is the study of obesity, body fat distribution, intramuscular fat and their role in insulin resistance with emphasis on the effects of weight loss and exercise training on muscle and glucose metabolism in sedentary, overweight individuals. The basic research includes the study of mechanisms by which diet and exercise interventions (aerobic and resistive training) affect skeletal muscle and adipose tissue metabolism, insulin signaling and gene expression in muscle, and in vivo insulin action in sedentary older individuals.
In addition, my research involves the study of residual hemiparesis following stroke which leads to physical deconditioning and possibly muscle atrophy and abnormal metabolism due to disuse or aberrant neural innervation. We have described skeletal muscle atrophy and greater fat deposition within the muscle of the hemiparetic limb in chronic hemiparetic stroke patients which may contribute to functional disability and increased cardiovascular disease risk in chronic hemiparetic stroke patients. We are currently examining the muscle molecular phenotype and its relationship to gait deficit severity and interventions designed to prevent muscle atrophy and reduce insulin resistance which are needed to minimize the loss of functional independence and cardiovascular disease risk in older chronically disabled stroke patients.
Obesity, Aging, Exercise Rehabilitation, Nutrition
Ryan AS, Ivey FM, Prior S, Li G, Hafer-Macko C. Skeletal muscle hypertrophy and muscle myostatin reduction after resistive training in stroke survivors. Stroke 2011; 42(2):416-420. PMCID: 3026882
Ryan AS, Ortmeyer HK, Sorkin JD. Exercise with calorie restriction improves insulin sensitivity and glycogen synthase activity in obese post-menopausal women with impaired glucose tolerance. Am J Physiol Endocrinol Metab. 2012;302:E145-152.
Ryan AS, Katzel LI, Prior SJ, McLenithan JC, Goldberg AP, Ortmeyer HK. Aerobic exercise plus weight loss improves insulin sensitivity and increases skeletal muscle glycogen synthase activity in older men. J Gerontol A Biol Sci Med Sci 2014; 69(7):790-8. PMID: 24357038
Addison O, Marcus RL, Lastayo PC, Ryan AS. Intermuscular Fat: A review of the consequences and causes. Int J Endocrinol 2014;309570. Epub 2014 Jan 8. PMID: 24527032
Prior SJ, Goldberg AP, Ortmeyer HK, Chin ER, Chen D, Blumenthal JB, Ryan AS. Increased skeletal muscle capillarization independently enhances insulin sensitivity in older adults after exercise training and detraining. Diabetes, 2015;64(10):3386-3395. PMID: 26068543
Griffith KA, Chung S, Zhu S, Ryan AS. Insulin resistance and inflammation in Black women with and without breast cancer: cause for concern. Ethn & Dis., 2016 26(4):513-520.
Serra MC, Goldberg AP, Ryan AS. Increased depression and metabolic risk in postmenopausal breast cancer survivors. Diabetology & Metabolic Syndrome. 2016; 8:44. PMID: 27453736
Ryan AS, Ivey FM, Serra MC, Hartstein J, Hafer-Macko CE. Sarcopenia and physical function in middle-aged and older stroke survivors. Archives of Physical Medicine and Rehabilitation, 2017; 98(3):495-499. PMID: 27530769.
Ortmeyer HO, Goldberg AP, Ryan AS. Exercise with weight loss improves adipose tissue and skeletal muscle markers of fatty acid metabolism in postmenopausal women. Obesity, 2017; 25(7): 1246-1253. PMID: 28547918
Addison O, Prior SJ, Kundi R, Gardner A, Ryan AS. Sarcopenia in peripheral arterial disease: Prevalence and impact on functional status. Archives of Physical Medicine and Rehabilitation. 2018:99(4):623-628. PMID: 29138051