Human Physiology

Space Physiology

Lighting to maintain circadian rhythm in space

Sleep deprivation and general well being is a major concern for long duration spaceflight, due to circadian rhythms often being misaligned. While lighting is a natural part of any habitat and spacecraft, this very ressource is underutilized in managing sleep. APL is researching wether a new programmable lighting system on the ISS can help restore circadian rhythm, increase well-being, reduce stress, and increase cognitive performance in cooperation with SAGA Space Architects.

Gravitational Effects on the Human Eye and Brain

Long-term exposure to microgravity environments have been associated with ocular changes and impaired visual acuity commonly referred to as Spaceflight Associated Neuro-ocular Syndrome (SANS). Research into SANS in the APL aims to further understand the pathophysiological mechanism behind the effects of weightlessness on the human eye.  


The GravitySuit provides a safe and mobile method to shift fluid from the upper body to the lower body by using lower body negative pressure (LBNP), a partial vacuum around the legs. Simultaneously, the suit generates a force from the shoulders to the feet, mimicing gravitational stress. Combined, these effects have a large potential in reverting some of the neuro-ocular, cardiovascular, and musculoskeletal deconditioning during long-term spaceflight.

Gravitational Effects on Muscle Strength and Mass

Entry into weightlessness causes both an immediate and a sustained cephalic shift of fluid and blood from the legs to the central circulation and in addition, sustained weightlessness with unloading of the weight-bearing muscles induces atrophy. In combination, these effects of weightlessness cause a reduction in leg circumference  known as “bird-leg syndrome”.

To better understand the development of this syndrome and to improve the current countermeasures, the Petersen Lab are testing next-generation wearables on board the International Space Station and on the ground. 

Effects of Weightlessness on the Musculo-Skeletal and Cardio Vascular System

The Aerospace Physiology Lab is currently part of two NASA projects designed to shed light on several negative physiological  effects of microgravity during prolonged space flight. 

Blood Volume Distribution in Weightlessness

Weightlessness can be created by letting an airplane undergo free fall following a parabolic trajectory. The Aerospace Physiology Lab utilizes this to investigate blood volume distribution in different vascular beds in relation to gravitational stress. 

Sports Medicine

Effects of Subconcussive Head Impacts in Soccer Players

Participation in head contact sports, such as soccer, has become increasingly linked to a higher risk of death from neurodegenerative disease and a range of neuropsychiatric issues. The Aerospace Physiology Lab investigates these concerns through research into head contact in sports and its effect on cerebral tissue and perfusion.