Poor quality and quantity of sleep is bad for us. This isn’t something science has to tell you, you can feel this in your body the morning after a night of short or poor sleep. But science is going to show you anyways. This time, in its effect on heart health, as published by a group of researchers from Uppsala University, lead Jonathan Cedernaes, in the journal Molecular Metabolism.

In this study, 16 young, healthy men were recruited and screened for existing cardiovascular and hereditary disease. They also had a normal sleeping habit of regularly sleeping 7 to 9 hours a night.

The participants were monitored in a sleep laboratory with standardized activity schedule and meals. Two sessions were conducted. In session one, participants got normal sleep three nights in a row. In session two, participants had disrupted sleep three nights in a row where they were kept awake half the night. Blood samples were taken in the morning and evening of every day. After each session, participants were put to thirty minute intense stationary cycling session.

Blood samples measure the NT-proBNP, a protein reflecting the stress on the heart, and troponin, a marker of cardiac muscle injury, such as that in a heart attack.

Troponin and NT-proBNP both increased after exercise as as expected. However, while NT-proBNP did not increase more after sleep restriction, troponin did and by approximately 40%. This indicates heart muscle injury during intense exercise when sleep has been disrupted for a prolonged period of time.

The authors concluded that chronic sleep deprivation lead to a lower threshold for heart injury during an intense bout of exercise.

Sleep isn’t for the weak. Sleep is for those who want to be strong and resilient.

T Marikainen et al. Effects of curtailed sleep on cardiac stress biomarkers following high-intensity exercise. Molecular Metabolism. https://doi.org/10.1016/j.molmet.2022.101445