Losing weight wasn't as hard as I had thought! =減量って思った程大変じゃなかったよ!
I shed pounds/ kilos without a problem =難なく何ポンド・キロも落とせたよ
Shed:(こそぎ)落とす
トレーナーさんのお陰で、と強調したい場合は以下のように言いましょう:
Thanks to my trainer, losing weight wasn't as hard as I had thought!
I shed 10 kilos without a problem because I had an amazing personal trainer
I couldn't have done it without my trainer =トレーナーなしでは達成出来なかった
My trainer is a life saver!=トレーナーに救われたよ!
色んな言い方があるので覚えやすいものを選んで使ってくださいね。