E4D combines four exercise modes: resistive training, cycling, rowing and rope pulling, offering a wide range of workouts and the flexibility to add new ones later.

“E4D is a gamechanger for astronaut health. By enabling a broader and more adaptable range of resistance exercises, it supports the preservation of muscle mass and bone integrity in microgravity which are two of the biggest physiological challenges during long‑duration missions,” says ESA’s E4D principal investigator Tobias Weber.

“Just as important is E4D’s self‑monitoring capability. Using an integrated camera-based motion capture system, it allows astronauts to track their performance, evaluate their movement execution and self‑correct posture in real time. This reduces reliance on ground supervision and helps ensure that every training session remains safe, precise and effective, even in the demanding environment of orbit,” adds Jennifer Struble, ESA’s Operations Team Lead for E4D and Co-Investigator.

“E4D is a system I’m really looking forward to using during the εpsilon mission. I really enjoy exercising for both physical and mental well-being and since it’s especially important to protect our bones and muscles in microgravity, I’m excited to try the new workouts made possible in space thanks to this European technology,” says ESA astronaut Sophie Sophie Adenot, who is now practising with E4D on the ground as part of her mission preparations.