Mitigation of detraining effects: physical activity improves protein profile and physical function of aged amid COVID-19.

Aim: We investigated the impact of abrupt interruption, imposed by COVID-19, and subsequent resumption of regular practice of a combined exercise training program on protein, renal profile, and physical functional capacity in physically active older adults before the pandemic.

Methods: Thirty-five volunteers (mean age 64.36 ± 19.43 years) participated, with data collected before the COVID-19 pandemic (PRE), 12 months after social isolation (PAN, detraining period), and 10 months after returning to regular exercise (POST).

Results: In the POST period, both older women (n = 26) and men (n = 9) exhibited higher serum levels of albumin and total protein (p < 0.0001 for albumin and total proteins in older women group; p = 0.0033 for albumin and p = 0.0002 for total proteins in older men group) compared to PRE and PAN. Older women showed, both at PAN and POST, elevated serum creatinine levels (p = 0.0309; p = 0.0003, respectively) and Timed Up and Go Test (TUGT) values (p = 0.0096; p = 0.0013, respectively), along with decreased estimated creatinine clearance in PAN (p = 0.0132; p = 0.0005, respectively) compared to PRE. Additionally, older women demonstrated lower gait speed (p = 0.0210) and muscle strength (p = 0.0002) in POST compared to PAN and PRE. Older men exhibited higher serum creatinine levels and estimated creatinine clearance in POST compared to PRE. Significant correlations between biochemical parameters, estimated creatinine clearance, and physical functional tests were observed, particularly in older women.

Conclusions: Overall, the study suggests that resuming combined exercise training partially mitigated the detraining-induced impairment in metabolic and physical capacities among older adults.