To learn more about what's happening on the International Space Station at any given time, check out NASA's frequently-updated ISS blog or their page about the research and development work happening on ISS.
Depends on your body type and metabolism and your routine. But usually it takes around 3 to 4 weeks for visible results. For me it took me a couple of months to actually see any progress visually.
How Long to Notice Muscle Gain? The time frame in which you can expect to notice muscle gain depends on several factors: your current fitness level, the intensity and consistency of your workouts and your body fat percentage. You may notice strength gains before you feel a change in muscle size, at which time you also should see visible results. According to the National Academy of Sports Medicine, those who are new to exercise can expect to notice muscle gain within four weeks of beginning a strength-training program.