NEW<\/span>You can now listen to Fox News articles!\n <\/p>\n<\/div>\n A former marathon runner who was diagnosed with the same condition as Celine Dion<\/a> worries that crowds could be a “trigger” during the singer\u2019s recently announced comeback.<\/p>\n Jon Kelf, 56, was a five-time marathon runner before he was diagnosed with stiff-person syndrome (SPS) in 2019, SWNS reported. Dion revealed her own diagnosis in late 2022.<\/p>\n SPS causes progressive muscle stiffness<\/a> and severe muscle spasms that can lead to chronic pain, falls and loss of mobility over time, according to UT Southwestern Medical Center.<\/p>\n UNEXPLAINED SHOULDER PAIN COULD SIGNAL DANGEROUS HEALTH CONDITION, DOCTOR WARNS<\/strong><\/a><\/p>\n “In some cases, spasms are so severe that they can cause falls, broken bones and dislocated joints,” the center notes on its website.<\/p>\n While this rare condition is not fatal, its symptoms can dramatically affect a person\u2019s quality of life.<\/p>\n Singer Celine Dion performs onstage during the 2017 Billboard Music Awards at T-Mobile Arena on May 21, 2017, in Las Vegas, Nevada.<\/span> (Ethan Miller\/Getty Images)<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n The disease is often triggered by emotional stress<\/a> or noise, elements Kelf calls “particularly debilitating.” He shared with SWNS that he never expected Dion to perform again.<\/p>\n LEANN RIMES\u2019 EMOTIONAL REACTION TO JAW RELEASE THERAPY SPARKS WIDESPREAD BUZZ<\/strong><\/a><\/p>\n \u00a0“I was a bit surprised. Especially when she talked about the dancing. I couldn\u2019t dance before the diagnosis, let alone afterwards,” said Kelf, who has no medical involvement or knowledge of Dion’s case personally.<\/p>\n “Obviously, she has the resources to get the best treatment<\/a> available, but even still, it\u2019s quite remarkable.”<\/p>\n BREAKTHROUGH ALS STUDY LAUNCHES AS DRUG AIMS TO SLOW DISEASE PROGRESSION<\/strong><\/a><\/p>\n In 2019, the former engineer started feeling his legs tighten up and stiffen anytime he was nervous or tense, but dismissed the odd sensations until one day, he stood and couldn’t move.<\/p>\n Kelf can now barely walk and has been forced to quit his job.<\/p>\n A former marathon runner with stiff-person syndrome said crowds could be a trigger for Dion’s comeback.<\/span> (Jon Kelf\u00a0)<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n Dion has announced 10 shows in September and October at the 40,000-capacity Paris la D\u00e9fense Arena, planned at three- to four-day intervals.\u00a0<\/p>\n The intervals will be crucial for Dion to pace herself, rest and medicate<\/a> between shows, according to Kelf.<\/p>\n CLICK HERE FOR MORE HEALTH STORIES<\/u><\/strong><\/a><\/p>\n “Everyone\u2019s different, but I\u2019m still surprised,” said Kelf, who added that the disease could “limit” the singer.<\/p>\n “It\u2019s challenging to live with, to say the least. You have to rearrange your entire life. There are good and bad days.”<\/p>\n CLICK HERE TO DOWNLOAD THE FOX NEWS APP<\/strong><\/a><\/p>\n While Kelf is hopeful that Dion will be able to make the show work, he warned against underestimating the seriousness of the disorder<\/a>.<\/p>\n Stiff-person syndrome causes stiffness of the limbs and muscles. Kelf can now barely walk and has been forced to quit his job.<\/span> (Jon Kelf \/ SWNS)<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n “I think it could undermine how seriously people take us, other sufferers,” he told SWNS.<\/p>\n While he views the tour as positive and inspiring, Kelf said he hopes it will lead to more support for others who are suffering.<\/p>\n![\"A](\"https:\/\/a57.foxnews.com\/static.foxnews.com\/foxnews.com\/content\/uploads\/2026\/04\/1200\/675\/man-celine-dion-disease.jpeg?ve=1&tl=1\")
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