There’s no boost like a workout boost and working out with friends, well, that takes it to the next level. Just as you’re more likely to go to a club if you know a friend’s going, science shows that working out with a friend increases your fitness, because you see in them a relatable goal. With a workout wife (who can have any relationship with you and be of any gender, we just love the level of commitment it implies), even if you’re not working out hand-in-hand, your motivation and achievements grow alongside your friendship.