I ran home covered in sweat even though its this cold outside.
"こんなに寒いのに汗だくで走ってっ帰ってきました"
- I ran home covered in sweat even though its this cold.
- Despite it being this cold outside, I ran home covered in sweat.
こんなに寒いのに - Despite it being this cold (outside); even though its this cold (outside)
汗だく - covered in sweat; sweaty
走ってっ帰ってきました - ran home
I can't believe I sweat so much in this cold running home from work.
It's hard to believe I sweat as much as I did running home from my friend's house in this cold weather.
この場合、次のような言い方ができますよ。
ーI can't believe I sweat so much in this cold running home from work.
「こんな寒いのに仕事から走って帰ってきて汗だくなんて信じられない」
to sweat so much「たくさん汗をかく・汗だくになる」
in this cold「この寒さの中」
ーIt's hard to believe I sweat as much as I did running home from my friend's house in this cold weather.
「この寒い中、友達の家から走って帰ってきてこんなに汗をかいて信じられない」
このような言い方もできます。
ご参考まで！
アメリカ合衆国 
カナダ 
