Higher level of physical activity reduces mental and neurological symptoms during and two years after COVID-19 infection in young women

Table of Contents

Characteristics of COVID-19 infection

In the study sample, 55.1% of the young women (n = 442) contracted SARS-CoV-2; 84.1% (n = 370) of them had a confirmed COVID-19 infection (PCR, RAT, IgG/IgM) and 63.8% (n = 277) received a diagnosis of COVID-19 by a healthcare worker during the acute COVID-19. 9 cases had symptomatic acute COVID-19. Based on the classification of WHO, in most cases, the severity of the COVID-19 infection was mild (86.7%, n = 358) (moderate: 12.8%, n = 53, severe: 0.5%, n = 2). 92.3% of the participants (n = 740) received a COVID-19 vaccine (Pfizer-BioNTech > 80%), most of them in two (45.7%, n = 336) or three (50.7%, n = 373) doses. The reinfection rate was 38% (n = 167), mostly after vaccination (82%, n = 137). 26.3% (n = 114) of the participants reported persisting, still present or intermittent symptoms. The average time since infection was 23.46 months (SD = 10.35, min: 1.48 − max: 50.10).

Characteristics of COVID-19 infection by level of PA

In sum, 42.9% (n = 344) of the women reported low, 34.8% (n = 279) moderate and 22.3% (n = 179) high PA. The prevalence of COVID-19 infection and the PA categories showed a significant moderate association (χ²(2,N = 802) = 6.433, p = 0.040, V = 0.09). A higher rate of COVID-19 infection was found in the moderate PA group (60.9%, n = 170) compared to the low (53.2%, n = 183) and high PA (49.7%, n = 89) groups.

The severity of the COVID-19 infection was mild in most cases regardless of the level of PA. However, the two severe cases showed low PA, and the rate of moderate severity was higher in the high PA group (20%, n = 16) than in the low PA (10.9%, n = 19) and moderate PA (11.3%, n = 18) groups.

Reinfection and PA did not show a statistically significant association (χ²(2,N = 440) = 3.978, p = 0.137, V = 0.10). Based on the frequency data, with a moderate effect, the rate of reinfection decreased with the increase in the level of PA (low PA: 43.3%, n = 78; moderate PA: 35.3%, n = 60; high PA: 32.2% n = 29). There was no statistically significant association between PCC and PA (χ²(2,N = 433) = 0.581, p = 0.748, V = 0.04). The prevalence of PCC was one-quarter regardless of the level of PA (low PA: 26.1%, n = 46; moderate PA: 28%, n = 47; high PA: 23.6 (n = 21).

Symptoms in acute COVID-19 by level of PA

During acute COVID-19, an average of 13.91 ± 10.41 (min = 1, max = 49) symptoms were reported; 10% of the cases (n = 44) were asymptomatic. The number of symptoms decreased with the level of PA (F(2,380) = 5.024, p = 0.007, η²_p = 0.03). The number of symptoms was the lowest in the high PA group (M = 11.64, SD = 10.79), while it was the highest in the low PA group (M = 15.88, SD = 10.79) and the number of symptoms was 13.12 (SD = 9.93) in the moderate PA group.

Most of the symptoms were neurological, mental and general, regardless of the level of PA (Fig. 1A). At the same time, the symptoms of these organ systems more frequently occurred in the low and moderate PA groups compared to the high PA group (Table 1).

Table 1 Frequency of symptoms of organ systems in acute COVID-19 in the total sample and the PA categories. Notes ENT-O: ear-nose-throat and ophthalmological symptoms.

In sum, the most frequently reported symptoms were fatigue (58.7%), anxiety (56.1%), dysmenorrhea (54.7%), depressed mood (53.3%), loss of interest/pleasure (52.6%), dizziness/light headedness (51.9%), trouble in concentrating (43.5%) and forgetfulness (43.2%). In the case of these symptoms, the frequency (%) was higher in the low and moderate PA groups compared to the high PA group (Fig. 2). For data on all the symptoms in the sample and the PA categories, see Supplementary File 1.

Symptoms in post COVID-19 condition by level of PA

In post COVID-19 condition, an average of 11.89 ± 8.60 (min = 1, max = 38) symptoms were experienced. The number of symptoms decreased in the high PA group (M = 8.12, SD = 7.66) compared to the low (M = 11.02, SD = 8.45) and moderate (M = 14.07, SD = 8.62) PA groups, after adjusting time since infection (F(2,102) = 3.474, p = 0.035, η²_p = 0.06). The majority of the symptoms were neurological, mental and general, regardless of the level of PA (Fig. 1B). At the same time, neurological and mental symptoms more frequently occurred in the low and moderate PA groups compared to the high PA group. In addition, the frequency of cardiovascular symptoms was higher in the moderate PA group than in the low and high PA groups (Table 2).

Table 2 Frequency of symptoms of organ systems in post COVID-19 condition in the total sample and the PA categories. Notes ENT-O: ear-nose-throat and ophthalmological symptoms.

In sum, the most frequently reported symptoms were fatigue (63.2%), dysmenorrhea (55.3%), loss of interest/pleasure (52.6%), dizziness/light headedness (51.3%), forgetfulness (46.1%), anxiety (43.9%), depressed mood (43%), palpitations (42.1%) and trouble in concentrating (40.9%). In the case of depressed mood, forgetfulness and dizziness/light headedness, a higher frequency was shown in the low and moderate PA groups compared to the high PA group, while in the case of the following symptoms, it was the moderate PA group which showed a higher frequency compared to the low and high PA groups: loss of interest/pleasure, anxiety and cardiovascular symptoms such as palpitations, chest pain, post-exercise malaise and reduced smell as well as shortness of breath (Fig. 3). For data on all the symptoms in the sample and the PA categories, see Supplementary File 2.

The frequently occurring symptoms also showed a tendency to co-occur in PCC, especially in the low and moderate PA groups (Fig. 4).

Finally, 68.8% of the symptoms in PCC were intermittent and 31.2% were still present with a lower rate in the moderate PA group (28.5%; low PA: 34.9%, high PA: 34.7%).

The number of symptoms in acute COVID-19 and PCC showed a positive moderate to large correlation in the low (r(40) = 0.511, p = 0.001) and moderate (r(44) = 0.798, p < 0.001) PA groups. In the case of the high PA group, there was a non-significant association (r(17) = 0.451, p = 0.069).

Functioning and changes in functioning based on the WHO Post COVID Case Report Form

Among participants who had contracted SARS-CoV-2, the total score of functioning was between 0 and 72.5 (M = 11.78, SD = 13.22), which means mostly no/mild difficulties in functioning. The total score of changes in functioning compared to the period before COVID-19 was between 0 and 100 (M = 53.86, SD = 10.82), meaning that mostly no deterioration was reported. Overall, only five participants (four in the low PA group, one in the high PA group) experienced both at least moderate difficulties (functioning ≥ 50) and a worsened status in functioning since COVID-19 (changes in functioning > 50). The most frequently occurred difficult and/or worsened functions with a decreasing tendency according to the level of PA were: being emotionally affected by health problems (F/Fch1), concentrating on doing something for ten minutes (F/Fch2), standing for long periods (F/Fch3), day-to-day school/work ((F/Fch4) (Fig. 5).