exhausting

It's exhausting to travel on the train with a lot of people around you.
大勢の人に囲まれて列車で旅をするのは疲れる。

I had an exhausting day today.
今日は大変な一日でした。

By attacking him, we're just needlessly exhausting ourselves.
彼を攻撃しても無駄に体力を消耗するばかりだ。

Competing in the political world must be exhausting work.
政界で競り合うのは大変な仕事に違いない。

I bet that was pretty exhausting.