probably doesn't mean '아마도', meaning maybe in Korean. It means 80% of possibility, doesn't it? So, as far as I'm concerned, you can say "지금 연습을 많이 하고계시는게 맞는거 같은데 휴식도 꼭 잘 취해 주셔야 되요."

you're probably practicing hard right now please make sure to rest well. 아마 지금 연습을 상당히 많이 하시는 것 같은데 휴식도 잘 취해셔야 돼요.