If I (o "eu" em inglês é sempre letra maiúscula) do exercise in the morning, my whole day will be very active and I won't feel any tired.

If I exercise in the morning, my whole day will be very active and I won't feel any tiredness.

If I do exercise in the morning my whole day will be very active and I won't get any tired.

If I exercise in the morning, my whole day will be very active and I won't feel tired.