In general, the body consumes a lot of water during physical activity, causing the body to become somewhat dehydrated, especially if the activity involves a lot of sweating.
When the percentage of body water in the body decreases, the percentage of body fat usually increases. Not because the amount of fat has actually increased, but because the proportions have changed.
When the amount of body water decreases, the result for muscle mass will also decrease, because the water in muscles is part of the result for muscle mass.
After physical activity, it is important to restore the amount of water in the body, but it may take some time for all water values in the body to return to normal. Therefore, we recommend waiting +/- 12 hours after intense physical activity to take a measurement.