In order to unlock an exercise, your friend needs to tap your link, then download Seven and open it directly from the App/Google Play Store page. Then they can create a profile and complete a workout 💪
You can find which exercises have been unlocked by going to Seven > Settings > Invite Friends. There you will see a list of your rewarded exercises.
Remember, inviting a friend unlocks individual exercises, not new workouts. You can use these exercises to boost your options in Freestyle or Custom workouts!