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 Update 9:12 p.m. ET: Bob Harper tweeted about his recent health scare, updating followers that he is indeed on the mend. "As you've heard, I had a heart attack 2 weeks ago. I'm on the mend now & want to thank everyone for the outpouring of messages and support.❤," the Biggest Loser fitness guru, 51, tweeted on Monday, February 27. 
 
 Original story continues below 
 
 As you've heard, I had a heart attack 2 weeks ago. I'm on the mend now & want to thank everyone for the outpouring of messages and support. 
 
 A close call! Biggest Loser fitness guru Bob Harper is “on the mend” after suffering a heart attack two weeks ago, a source tells Us Weekly. 
 
 “It is very scary but runs in his family,” the insider said of Harper, 51, who has appeared as a trainer on the hit NBC reality weight-loss competition for all 17 seasons. (The trainer told TMZ that his mother had died of a heart attack.) But a second source tells Us that genetics may not be the only factor, and worries that the star “pushes himself too hard.” 
 
 As first reported by TMZ, Harper was working out an NYC gym about two weeks ago when he collapsed. A fellow gym-goer who also happened to be a doctor administered CPR and used paddles to keep the trainer alive. 
 
 Jimi Celeste/Patrick McMullan via Getty Images 
 
 Harper was then taken to the hospital, where he regained consciousness two days later. He spent a total of eight days in the hospital, according to TMZ, and is still in NYC since his doctor has not yet cleared him to fly back home to Los Angeles. 
 
 My word of the day... LUCKY A post shared by Bob Harper (@trainerbob) on Feb 22, 2017 at 4:48am PST 
 
 On Wednesday, February 22, the reality TV personality posted a cryptic photo to Instagram, of a candle and a stack of photos on a wooden table. “My word of the day... LUCKY,” he captioned the picture. 
 
 Harper, who previously competed against fellow fitness trainer Jillian Michaels on the show, became the host of The Biggest Loser in 2015 after Alison Sweeney vacated the role. 
 
 
 
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 Bob Harper Suffers Serious Heart Attack 
 
 Bob Harper Suffers Serious Heart Attack 
 
 EXCLUSIVE 
 
 Bob Harper -- a fitness guru who's the host of "The Biggest Loser" -- suffered a heart attack that left him unconscious for 2 days. 
 
 Harper tells us he was working out in a NYC gym 2 weeks ago when he collapsed. A doctor who was also working out administered CPR and used paddles to keep Bob alive. 
 
 The 51-year-old was taken to the hospital and says he woke up 2 days later. He was hospitalized for 8 days and is still in NYC -- he lives in L.A. -- because his doctors have not cleared him to fly. 
 
 He's doing a lot better and his exercise for the time being is limited to walking. 
 
 Bob -- a fitness nut -- says the heart attack is all genetics. His mom died from a heart attack. 
 
 Glad he's on the mend. 

 NBC announced that veteran trainer Bob Harper will be replacing Alison Sweeney on the upcoming 17th season of The Biggest Loser Credit: Chris Haston/NBC/NBCU Photo Bank via Getty Images 
 
 Bob Harper will be wearing two hats, figuratively speaking, when The Biggest Loser returns for its upcoming 17th season. As announced by NBC on Tuesday, Sept. 8, the veteran trainer is replacing Alison Sweeney as host of the weight-loss competition. 
 
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 "I'm super excited about taking the position of host on The Biggest Loser," Harper, 50, said in a press release about the news. "I've been with the show since Season 1, so I know all of the ins and outs, and let me tell you, the weigh-in room is going to be a completely different ballgame with me at the steering wheel." 
 
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 According to the release, Harper will still "offer his training expertise to contestants at various points throughout the season," but he'll also be guiding them "through all weigh-ins, challenges, and temptations." Returning stars Dolvett Quince and Jennifer Widerstrom will be the primary trainers. 
 
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 The news comes after Sweeney's announcement last month that she would not be returning to the franchise for the upcoming cycle. The Days of Our Lives actress, 38, joined the show before 2007's Season 4, and has led 13 groups of contestants since then. 
 
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 Harper, meanwhile, started as a trainer on The Biggest Loser back in 2004. He is the only person who has been with series since its debut. 
 
 Season 17 of The Biggest Loser begins filming this month. Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics, and more delivered straight to your inbox!
– Fitness trainer Bob Harper, host of NBC's The Biggest Loser, says he's recovering from a serious heart attack that left him unconscious for two days, the AP reports. Harper tells TMZ he was working out in a gym in New York City this month when he collapsed. He says a doctor who also was in the gym performed CPR on him. The 51-year-old Harper says he spent eight days in a New York hospital and hasn't yet been cleared to fly home to Los Angeles. Harper adds that it's his genes, not his lifestyle, that led to his heart attack: His mom died from a heart attack. But a source tells Us Weekly the fitness buff "pushes himself too hard," which the source feels may have contributed to the attack. On Wednesday, Harper posted a pic of a scented candle burning on Instagram with the caption, "My word of the day ... LUCKY." Harper has been a fixture on all 17 seasons of The Biggest Loser. He served as a trainer on the show from 2004 to 2015 and took over hosting responsibilities for the reality-TV weight-loss program from Alison Sweeney in 2015.