A Moderate-length Exercise Training Intervention Reduces Serum Protein Status In Older Adults

Abstract

Chronic exercise programs improve cardiometabolic status, lipid profile and glycemic control in older adults. These interventions usually last between 15 to 24 weeks with a frequency of three to four times per week, jeopardizing the older adult continuous interest in the program and eventually its adherence. PURPOSE: To determine the effect of a moderate-length exercise program on metabolic and protein status older adults. METHODS: Thirty-five volunteers (age= 62.6±7.3 yr., BMI= 28.3±3.9 kg/m2, Body fat = 39.8±7.1%) completed the exercise program. Measures of body composition (body fat, BMI, muscle mass [MM] and muscle index [Mindex]), serum total proteins (TP), albumin (ALB), glucose (GLU), triglycerides (TG), total cholesterol (TC), 6-min walking test (6MWT), and estimated VO2max were recorded before and after completion of the program. Each training session was performed for 50-min at moderate intensity (12 to 14 on Borg’s RPE scale), with three-days of aerobic exercise and two-days of resistance training, accumulating five sessions per week for 12 weeks. Paired Student’s t-tests with Cohen’s d effect sizes were computed on JASP v0.9.2 software. RESULTS: No significant changes were observed on BMI (Pre= 28.3 ± 3.9 vs. Post= 28.6 ± 4.2 kg/m2, p= 0.067, d= -0.35), body fat (Pre= 39.8 ± 7.1 vs. Post= 40.1 ± 7.4%, p= 0.63, d= -0.09), MM (Pre= 22.7 ± 4.1 vs. Post= 22.8 ± 4.1 kg, p= 0.15, d= -0.27), Mindex (Pre= 9.1 ± 0.9 vs. Post= 8.0 ± 3.1 kg/m2, p= 0.059, d= 0.34), TC (Pre= 183.2 ± 68.9 vs. Post= 175.8 ± 115 mg/dL, p= 0.70, d= 0.06), 6MWT distance (Pre= 480.7 ± 105.7 vs. Post= 461.8 ± 123.6 m, p= 0.9, d= 0.02) and VO2max (Pre= 29.4 ± 6.9 vs Post= 28 ± 7.1 mL•kg-1•min-1, p= 0.46, d= 0.13). Significant reductions were found on GLU (Pre= 98.0 ± 54.4 vs. Post= 77.5 ± 45.3, p= 0.011, d= 0.45), TG (Pre= 122.2 ± 82.0 vs. Post= 99.5 ± 66.5 mg/dL, p= 0.05, d= 0.34), TP (Pre= 6.5 ± 2.6 vs. Post= 4.3 ± 1.5 mg/dL, p= 0.0001, d= 0.90), and ALB (Pre= 3.7 ± 1 vs. Post= 2.9 ± 0.9 mg/dL, p= 0.0001, d= 0.80). CONCLUSION: A moderate-length 12-week exercise program improved GLU and TG levels in older adults. The lowered TP and ALB with a concomitant trend of the Mindex reduction suggest a metabolic overreaching tending to undernutrition after the program.