Introduction
Material and methods
Study population and investigation period
Examination of symptoms
Anthropometric data | Fatigue symptoms (FS) | No fatigue symptoms (NFS) | Differences between both groups |
---|---|---|---|
Mean ± standard deviation | Mean ± standard deviation | p-value (Cramer-V) | |
Age (years) | 37.1 ± 12.5 | 30.0 ± 10.0 | 0.006** |
Body mass (BM) (kg) | 77.1 ± 16.9 | 75.5 ± 13.5 | 0.736 |
Height (cm) | 174.9 ± 9.3 | 179.0 ± 8.5 | 0.037* |
Body mass index (BMI) (kg/m2) | 25.05 ± 4.0 | 23.6 ± 3.0 | 0.070 |
Sex | F: 21, M: 21 | F: 13, M: 30 | 0.064 |
Time since infection (months) | 6.3 ± 5.4 | 2.5 ± 2.6 | < 0.001**** |
Type of sportsa | Frequency | Frequency | |
Endurance | 29 (59.2%) | 21 (42.0%) | |
Resistance | 7 (14.3%) | 11 (22.0%) | |
Team/combat | 10 (20.4%) | 16 (32.0%) | |
Technique | 3 (6.1%) | 0 | |
Missing | 0 | 2 (4.0%) | |
Weekly training volume before disease | Number | Number | |
3–5 h | 26 (61.9%) | 14 (32.6%) | |
5–10 h | 11 (26.2%) | 16 (37.2%) | |
10–15 h | 1 (2.4%) | 7 (16.3%) | |
> 15 h | 3 (7.1%) | 6 (14.0%) | |
Missing | 1 (2.4%) | 0 | |
Symptoms during acute phasea | Frequency | Frequency | |
Fever (> 38 °C) | 15 | 18 | 0.543 (0.037) |
Cough | 13 | 19 | 0.181 (0.161) |
Ageusia/anosmia | 15 | 19 | 0.398 (0.102) |
Rhinitis | 16 | 21 | 0.281 (0.130) |
Throat pain | 20 | 16 | 0.276 (0.131) |
Dyspnea under load | 19 | 10 | 0.022* (0.277) |
Dyspnea at rest | 12 | 4 | 0.019* (0.283) |
Diarrhea | 7 | 7 | 0.952 (0.007) |
Headache | 17 | 22 | 0.281 (0.130) |
Missing | 8 | 8 | |
Further persistent symptomsa | Frequency | Frequency | |
Sleeping disorders | 20 | 10 | 0.019* (0.255) |
Neurocognitive disorders | 28 | 9 | < 0.001**** (0.461) |
Respiratory disorders | 21 | 5 | < 0.001**** (0.416) |
Autonomic disorders | 23 | 9 | 0.001*** (0.349) |
Muscle pain | 14 | 4 | 0.007** (0.294) |
Psychological-related items | 1 | 0 | 0.314 (0.110) |
Immunological disorders | 8 | 1 | 0.012* (0.272) |
No symptoms | 0 | 22 | |
Lung involvement at examination | |||
Minimal abnormalities in body plethysmography | 4 (9.5%) | 2 (4.7%) | |
Minimal abnormalities in spirometry | 1 (2.3%) | 1 (2.3%) | |
Minimal abnormalities in diffusion capacity | 7 (16.7%) | 1 (2.3%) | |
Abnormalities in body plethysmography | 3 (7.1%) | 1 (2.3%) | |
Abnormalities in spirometry | 4 (9.5%) | 1 (2.3%) | |
Abnormalities in diffusion capacity | 2 (4.7%) | 0 |
Examination of CPET and lactate determination
Criteria for total exhaustion
Statistical analysis
Results
Differences between FS and NFS regarding symptoms
Differences between FS and NFS regarding exhaustion variables
Determination of total exhaustion
Exhaustion criterion | Absolute number of individuals who reached the exhaustion criterion (relative number in %) | Differences between both groups | |
---|---|---|---|
Fatigue symptoms | No fatigue symptoms | p-value (Cramer-V) | |
Plateau of HR | 5 (13.5%) | 6 (16.2%) | 0.744 (0.038) |
Reaching maximum HR | 16 (43.2%) | 20 (55.6%) | 0.346 (0.111) |
Plateau of V̇O2 | 10 (26.3%) | 12 (30.8%) | 0.665 (0.049) |
Peak RER ≥ 1.15 | 29 (74.4%) | 35 (89.7%) | 0.077 (0.200) |
Peak VE/ V̇O2 ≥ 35 | 28 (71.8%) | 27 (69.2%) | 0.804 (0.028) |
Peak BF ≥ 50 | 4 (10.3%) | 7 (17.9%) | 0.329 (0.111) |
Max. lactate > 10 mmol/l | 26 (61.9%) | 37 (86.0%) | 0.011* (0.276) |
Perceived subjective general exhaustion ≥ 9 | 33 (82.9%) | 30 (76.9%) | 0.412 (0.092) |