SOCIAL MEDIATikTokViral Challenges WARNING: TikTok “75 Hard” Fitness Challenge Potentially Dangerous by Skyler Romero October 20, 2021 by Skyler Romero October 20, 2021 The TikTok “75 Hard” Challenge has users working out and dieting hard, but some experts wonder whether it’s safe. Get the story here. 0 FacebookTwitterPinterestEmail