To complete the “Handstand T Shirt Challenge,” you need to put a t-shirt onto your body while doing a handstand. The person completing the challenge gets onto their hands next to a wall, then props their feet up so that their toes rest against the wall. Next, they take one arm at a time to get the shirt over their arms and heads. Once the shirt is completely over their arms and head, they can release from the handstand to pull the shirt down over their chest and stomach. This challenge requires you to hold a handstand for a good deal of time; though some buff celebrities were able to do it in a matter of seconds, others who have taken the challenge needed a few minutes to get the shirt on. Thus, this challenge requires a certain degree of athleticism and is definitely impossible for many people, particularly those who are not able-bodied or who simply are not very physically fit. Some notable celebrities who have taken part in this challenge are Tom Holland, Jake Gyllenhaal, Maggie Gyllenhaal. American Olympian Lolo Jones raised the stakes by putting two shirts on instead of one, and then taking a sip of wine from a glass while still balancing on one hand. This challenge is popular for how funny it is watching people struggle to balance on one hand at the same time as they try to pull a shirt on. Additionally, people like to record short segments before or after the challenge where they talk about the challenge and nominate other people to give it a shot. Some people who were nominated for the challenge but who were incapable of doing a handstand, such as Ryan Reynolds, chose to make video responses to their nominations instead, where they talk and crack some jokes. 
The Handstand Challenge can only be completed by people in very good physical shape, and even then, many will not have the strength or coordination to complete it. While this does make the challenge more difficult than others, and thus maybe more gratifying to complete, it also makes the pool of possible participants in this challenge very small. It's highly unlikely that most people could participate in this challenge, which definitely has stifled its popularity. If you're not a super athletic person, this challenge holds no appeal, as physical fitness is really the only thing this challenge is based on. If we consider the amount of people who participate in a challenge and its subsequent popularity to be relevant to the challenge's success, then this is not the most successful challenge.