Fatigue in Covid-19 survivors: The potential impact of a nutritional supplement on muscle strength and function

Background: Fatigue with reduced tolerance to exercise is a common persistent long-lasting feature\r\namongst COVID-19 survivors. The assessment of muscle function in this category of patients is often\r\nneglected.\r\nAim.: To evaluate the potential impact of a daily supplementation based on amino acids, minerals, vi-\r\ntamins, and plant extracts (Apportal®) on muscle function, body composition, laboratory parameters and\r\nself-rated health in a small group of COVID-19 survivors affected by fatigue.\r\nMethods: Thirty participants were enrolled among patients affected by physical fatigue during or after\r\nacute COVID-19 and admitted to the post-COVID-19 outpatient service at Fondazione Policlinico Gemelli\r\nin Rome between 1st March 2021 and 30th April 2021. All participants were evaluated at first visit (t0)\r\nand at control visit (t1), after taking a daily sachet of Apportal® for 28 days. Muscle function was\r\nanalyzed using hand grip strength test, exhaustion strength time and the number of repetitions at one-\r\nminute chair stand test. Body composition was assessed with bioelectrical impedance analysis (BIA).\r\nLaboratory parameters, including standard blood biochemistry and ferritin levels, were evaluated at the\r\nfirst visit and during the control visit. A quick evaluation of self-rated health, before COVID-19, at t0 and\r\nt1, was obtained through a visual analogue scale (VAS).\r\nResults: Participants aged 60 years and older were 13 (43%). Females represented the 70% of the study\r\nsample. Participants hospitalized for COVID-19 with low-flow oxygen supplementation represented the\r\n43.3% of the study sample while 3.3% received noninvasive ventilation (NIV) or invasive ventilation. Hand\r\ngrip strength improved from 26.3 Kg to 28.9 Kg (p < 0.05) at t1 as compared to t0. The mean time of\r\nstrength exhaustion increased from 31.7 s (sec) at t0 to 47.5 s at t1 (p < 0.05). Participants performed a\r\nhigher number of repetitions (28.3 vs. 22.0; p < 0.05) during the one-minute chair stand test at t1 as\r\ncompared to t0. A trend, although not significant, in reduction of ferritin levels was found after nutri-\r\ntional supplementation (94.4 vs. 84.3, respectively; p ¼ 0.01). The self-rated health status increased by at\r\nleast 13 points (t0, mean 57.6 ± 5.86; t1, mean 71.4 ± 6.73; p < 0.05).\r\nConclusions: After 28 days of nutritional supplementation with Apportal® in COVID-19 survivors affected\r\nby fatigue with reduced tolerance to exercise, we found a significant improvement in means of muscle\r\nstrength and physical performance, associated with enhancement of self-rated health status between t0 and t.