Andrew Lloyd en collega's onderzochten de invloed van fysieke en mentale inspanning op

'vermoeidheid', activiteit, slaap (duur en kwaliteit), en hartslag(variabiliteit) bij 25 CVS-patiënten.

Uiteraard nam de "vermoeidheid" langdurig toe na inspanning (minstens 24 uur).

Ook brachten de patiënten (overdag) meer uren liggend door na de inspanning.

De inspanning had tevens invloed op de afname van de hartslagvariabiliteit van wakkere naar

slapende toestand. Die toename van de hartslagvariabiliteit, die gebruikelijk is als het lichaam in een rust-toestand komt (zie afbeelding onder) nam na de (fysieke en mentale) inspanning beduidend af.

Dit zou kunnen betekenen dat het lichaam na een inspanning minder tot rust komt tijdens de slaap.

Vreemd genoeg (of niet?) nam het aantal uren slaap niet toe en de kwaliteit van de slaap niet af.

Autonomic nervous system function, activity patterns, and sleep after physical or cognitive challenge in people with chronic fatigue syndrome.

J Psychosom Res. 2017 Oct 19. doi: 10.1016/j.jpsychores.2017.10.010

Cvejic E Sandler CX, Keech A, Barry BK, Lloyd AR, Vollmer-Conna U.

Highlights

• Substantive and prolonged exacerbation of fatigue was triggered by physical or cognitive challenges.
• A greater proportion of daytime hours were spent lying down post-challenge.
• Sleep duration and quality were comparable pre- and post-challenge.
• Nocturnal parasympathetic activity was reduced post-challenge.

Abstract

Objective

To explore changes in autonomic functioning, sleep, and physical activity

during a post-exertional symptom exacerbation induced by physical or cognitive challenge

in participants with chronic fatigue syndrome (CFS).

Methods

Thirty-five participants with CFS reported fatigue levels

24-h before, immediately before, immediately after, and 24-h after the completion of

previously characterised physical (stationary cycling) or cognitive (simulated driving) challenges.

Participants also provided ratings of their sleep quality and sleep duration

for the night before, and after, the challenge.

Continuous ambulatory electrocardiography (ECG) and physical activity

was recorded from 24-h prior, until 24-h after, the challenge.

Heart rate (HR) and HR variability (HRV, as high frequency power in normalized units)

was derived from the ECG trace for periods of wake and sleep.

Results

Both physical and cognitive challenges induced

an immediate exacerbation of the fatigue state (p < 0.001),

which remained elevated 24-h post-challenge.

After completing the challenges,

participants spent a greater proportion of wakeful hours lying down (p = 0.024),

but did not experience significant changes in sleep quality or sleep duration.

Although the normal changes in HR and HRV

during the transition from wakefulness to sleep were evident,

the magnitude of the increase in HRV was significantly lower

after completing the challenge (p = 0.016).

Conclusion

Preliminary evidence of

reduced nocturnal parasympathetic activity, and increased periods of inactivity,

we found during post-exertional fatigue in a well-defined group of participants with CFS.

Larger studies employing challenge paradigms are warranted to further explore

the underlying pathophysiological mechanisms of post-exertional fatigue in CFS.

Keywords

Chronic fatigue syndrome, post-exertional fatigue, heart rate, variability, parasympathetic, sleep