Background: Variations in genotype may contribute to heterogeneity in functional adaptations to exercise. Methods: A systematic search of eight databases was conducted, and 9,696 citations were screened. Results: Eight citations from seven studies measuring 10 single-nucleotide polymorphisms and nine different functional performance test outcomes were included in the review. There was one observational study of physical activity and six experimental studies of aerobic or resistance training. The ACE (D) allele, ACTN3 (RR) genotype, UCP2 (GG) genotype, IL-6-174 (GG) genotype, TNF-α-308 (GG) genotype, and IL-10-1082 (GG) genotype all predicted significantly superior adaptations in at least one functional outcome in older men and women after prescribed exercise or in those with higher levels of physical activity. Conclusion: There is a small amount of evidence that older adults may have better functional outcomes after exercise/physical activity if they have specific alleles related to musculoskeletal function or inflammation. However, more robust trials are needed.
Guy C. Wilson, Yorgi Mavros, Lotti Tajouri and Maria Fiatarone Singh
Marjan Mosalman Haghighi, Yorgi Mavros and Maria A. Fiatarone Singh
Background: Systematically evaluate the effects of structured exercise and behavioral intervention (physical activity [PA] alone/PA + diet) on long-term PA in type 2 diabetes. Methods: Systematic search of 11 databases (inception to March, 2017). Randomized controlled trials investigating structured exercise/behavioral interventions in type 2 diabetes reporting PA outcomes ≥6 months were selected. Results: Among 107,797 citations retrieved, 23 randomized controlled trials (including 18 behavioral programs and 5 structured exercise) met inclusion criteria (n = 9640, 43.6% men, age = 60.0 (4.0) y). All structured exercise trials demonstrated increased objective PA outcomes relative to control (pooling was inappropriate; I 2 = 92%). Of 18 behavioral interventions, 10 increased PA significantly, with effect sizes ranging from 0.2 to 6.6 (pooling was inappropriate; I 2 = 96%). After removing 1 outlier, the remaining 17 studies significantly improved PA (pooled effect size = 0.34), although smaller compared with structured exercise. After removing the outlier, meta-regression also revealed significant direct relationships between total contacts (r = .50, P < .01) and more face-to-face counseling (r = .75, P < .001) and increased PA. However, long-term changes in PA and HbA1c were not related. Conclusion: Both structured exercise and behavioral interventions increased PA in type 2 diabetes, although effect sizes were larger for supervised exercise. The effectiveness of behavioral programs was improved when delivery included more extensive and face-to-face contact.