With both kids, I started working out again at 16 days postpartum, but I treated myself with kindness, doing mild workouts, because my fitness level was lower. ↗
At least for soccer players, it comes down to a blend of two types of fitness - your base endurance, which comes from longer distance running, and your speed, which comes from sprint-based workouts. ↗
If I'm on holiday, I'm active on the beach, I play tennis, I run, I swim a lot. It's just about making the workouts fun, I think, and then it doesn't really feel that bad. ↗