He wants you to work out more. Jerk.

That would bug me, OP. Can you return them and get something you want?

Grounds for divorce.

Are you always such a PITA?

Lady. Unclench. There is nothing hotter then
When I see my wife in her yoga pants.

Game on.

Put your new yoga pants on, and get your game on.

My first thought is that's he's telling you to lose weight

Maybe it's a hint. Did you gain weight?

Humblebrag

Don't look a gift horse....

Maybe he was being selfish and got you something that turns him on. Could be worse.

His laugh and "well if you did..." indicate to me that he didn't really believe you when you said you didn't want them. Especially because you answered his question about the size. Be more clear.

Sometimes people do this with gifts, "oh don't get me anything, I don't really want that", etc. and the fact that he got you more than one of the outfits shows he truly thought you meant something other than what you said.

Does this guy have a fetish for these clothes or something?

Maybe he had already bought them and was just confirming the size was right? Or maybe he thought you deserved to treat yourself to new workout clothes? My husband does this. He has good intentions, so I just shrug it off and thank him. My last birthday he bought me an expensive cake from a bakery I specifically told him I didn't like. He thought I said I didn't like it because I didn't want him to spend too much money on cake.

Happy Birthday!
He must have gotten them before asking the question?
Just go out and get something you really want but be happy you have extra sets for raining days!

Two weeks ago my husband asked me what size workout pants I wore, he asked if I needed an xs/s. I said "I'm not sure, I don't really want any workout clothes tho." He laughed and said well if you did what size, I told him I guessed a small. Today is my birthday and he got me 2 pairs of athletic leggings and 2 workout shorts. The one thing I didn't want, and he spent a lot of money on it. I literally told him, I didn't want/need workout clothes. He keeps asking me if I tried them on, and thought I would be excited. He isn't generally this clueless.