Research Information System
MEDICINA (KAUNAS, LITHUANIA), vol.61, no.1, pp.86-99, 2025 (SCI-Expanded)
Abstract: Background and Objectives: Long COVID-19 syndrome may cause difficulties
in functionality during daily life in young people. Our objective was to investigate the
respiratory and functional sequelae in young adults with asymptomatic or mild COVID-19
compared with healthy peers 3–6 months and 6–12 months after COVID-19 infection. Materials
and Methods: Participants aged 18–25 who had COVID-19 within the last 3–6 months
(Post-COVID Group 1, n = 25) and 6–12 months (Post-COVID Group 2, n = 25) and age–
gender-matched healthy controls (n = 25) were included in this study. Respiratory functions
and muscle strength were measured. Physical function was assessed with 6 min walking
test (6MWT) and an Incremental Shuttle Walk Test (ISWT). The 1 min sit-to-stand
test (1-MSTST) and hand grip strength (HGS) were used to assess muscle performance.
Fatigue and dyspnea severity were questioned. Results: The FVC%pred (p = 0.023) and
MEP (p = 0.034) were higher, and 1-MSTST repetitions were lower in Post-COVID Group-1
compared to Post-COVID Group-2 (p = 0.029). The PEF%pred (p = 0.025), MEP (p = 0.001),
and ISWT distance were lower in Post-COVID Group-2 compared to healthy controls. The
number of 1-MSTST repetitions and 6MWT distance were lower in Post-COVID Group-1
(p = 0.003, p = 0.001) and Post-COVID Group-2 (p = 0.003, p = 0.017) than in healthy controls.
Exercise-induced blood lactate change during the ISWT, HGS, fatigue, and dyspnea were
not significantly different between post-COVID groups and healthy controls. Conclusions:
Young adults who pass asymptomatic or mild SARS-CoV-2 infection exhibit a decline in
FVC%pred, PEF%pred, lower extremity muscle performance, and physical function within
3–6 months. In addition, the deterioration in respiratory and physical functions becomes
apparent within 6–12 months.