Similar to liking a Facebook post or favoriting a tweet, kudos are a quick thumbs-up you can give to your fellow athletes to congratulate them on a noteworthy activity, achievement, post, badge, or challenge milestone. You can see how many kudos have already been given from your feed and add your own. You can also give kudos directly from the activity page or athlete post. Once you give kudos, the icon will turn orange. To see the list of athletes who have previously given kudos, click on the number next to the kudos icon. You can manage your kudos notification preferences in your settings.
Can I undo or delete a kudos?
There is no way to "undo" or remove kudos. Strava's all about celebrating the effort, and just like a high-five or popping the podium champagne, once it's happened, it's happened. No take-backs!