Hey there, welcome to Paging Dr. Gupta. Thanks so much for joining us. We got a lot of questions that came in this week, so I'm gonna dive right in. Jesse's with us. Who do we have first?

Hey, Sanjay. So as you know, the Seattle Seahawks just won the Super Bowl and we have a bunch of questions related to the big game, mostly about playing sports on turf or grass. So Sarah from Colorado asks, my daughter has seen a shift from playing soccer on mostly grass fields to almost all turf fields. How do rates of minor injury compare on the two surfaces?

Okay Sarah, thank you for the question. First of all, I can tell you that I've noticed this same transition with my own kids. A lot more turf fields as compared to mostly grass fields when I was growing up. And I think it's smart to ask if that's really the safest option for our children. So I've done a lot of reporting on this topic. I'm a doctor, but I'm also a sports fan. I talked to a lot folks at the NFL who are looking into this. And I can you this grass vs. Turf debate is one of the big ones that's happening in professional sports, so I'll share with you what I know right after the break. Okay, we're talking about how often minor athletes get injured playing on turf fields compared to grass fields, youth soccer specifically. So the Academy of Pediatrics, first of all, they recently reaffirmed the findings of this big review of soccer injuries. And the headline was, recent studies have shown no difference in overall injury rates during games that are played on grass or turf. And I'm highlighting the word games here as opposed to practices because lower extremity injury rates were higher during training, during practices, actually on grass. I think that surprised a lot of people. So again, during games between turf and grass, not a huge difference. But during practices and training, grass ended up being associated with more injuries. In fact, according to a 2016 study, they found kids playing soccer who got injuries were almost twice as likely to have been playing on grass I think part of the reason here is that for youth soccer, the surfaces may not be maintained as well, especially during practices. So there may be divots in the grass, there may water pooling, there may uneven surfaces, and that is probably what's leading to more injuries on the grass during practices, I think the message for parents here is you gotta make sure you're checking the condition of the field before playing. Whether it is game or it is practice, checking for debris or holes or excess water, those things can cause injury, addressing them ahead of time can prevent the injury.

Okay, great. And Mike wants to know, are the types of injuries consistent across both types of fields?

'Right, so that's the next big question. There was this big review of the scientific literature. 53 articles published over nearly 50 years, between 1972 and 2020. Keep in mind, turf really came about in the mid-1960s. It was used before that, but it became quite popular at the Astro Dome, which is why the first turf was called Astro Turf. And now all sports, all levels of competition, all turf types have been included in these various studies. Some of the early studies, the early days, I think it's fair to say that the turf wasn't that good. It just wasn't good and there were a lot more injuries. Over the years, the turf has improved. It's become more like grass. So what's interesting is that if you look at the overall number of injuries on turf versus grass, they're about the same. But if you start to zero in on the body part, a different picture starts to emerge. So, for example, foot and ankle injuries. Higher on artificial turf compared with grass. Knee and hip injuries about the same, turf or grass. But just about all other injuries more common on grass. So overall number of injuries around the same. Foot and ankle injuries more comment on turf. Bear in mind this is a broad review and when you zero in on specific sports or smaller populations, you may get slightly different answers to this question.

All right, last question on this topic. It comes from Anna in Liberty, Missouri. She wrote in: My understanding is that artificial fields in all sports are dressed up with ground tire rubber. You see some kind of particles flying up during games, but aren't rubber tires classed as a carcinogen?

Yeah, and I love this question. I think this is a valid concern talking about crumb rubber specifically if you've watched games You've seen those black particles sort of fly up when someone gets tackled. I had a chance to talk to Nick Pappas. He's the guy who is the field director for the NFL. He determines field surfaces for big games including the Super Bowl. He was the guy that determined that grass would be used for the Superbowl and that that grass would be Bermuda grass. It was grown over 18 months at a sod farm. He's the guy that does all this. He's very familiar with surfaces, and here's what he told me.

What's the concern about toxicity? When I was looking in this, they said, if I touch this stuff, I should wash my hands immediately after.

From our perspective, working closely with the manufacturers, working with our own specialized individuals on the NFL and NFLPA side, we don't have any concerns over toxicity right now. There's obviously, anytime you're out in the elements, there's, you know, you're within whatever's around you, but here, whether you're inside or outside, we haven't run into any concerns with toxicity from a crumb rubber perspective or any of our natural infills or the various infills that are out there.

'Okay, so valid concern, because we're talking about crumb rubber, which comes from recycled tires. Recycled tires contain carcinogens, cancer-causing agents. So the question is, is that going to be a problem? And I think what Nick is saying is that if you look at the population studies, and you look a people who have a lot of exposure to turf, they're not seeing an impact. They're not seeing people get sick or develop other problems as a result of lots of exposure to turf. So at the population level, there's been no data suggesting a cause and effect relationship between turf and some of these medical problems. This is a really fascinating issue and no surprise, we got so many questions. Thanks for those questions. We're gonna take a quick break. When we come back, we're gonna talk about the role exercise plays in preventing neurodegenerative diseases. We'll be right back. All right, that sound means we're back. Jesse, who's up next?

Okay, so we're gonna stick with our sports theme today. Sahar in DC is 24 years old, and she's followed your reporting on the role exercise plays in battling dementia. But she's wondering if there's more to the story.

'I've recently gotten into exercising regularly, and I know that it plays a very important part in keeping sharp. And I'm just worried a little bit about the recent links to long-term strenuous exercise marathon running when it comes to other neurodegenerative diseases like Parkinson's or ALS. And I just wanted to know your thoughts on that. Can this long- term intensive exercise increase your risk for those diseases? Thank you so much.

'All right, Sahar, first of all, as a fellow runner, I hear you. The idea that something as healthy as exercise could have this dark side, that's alarming, obviously. But like most things in medicine, the answer is not a simple yes or no. Think about the dose and think about your own biology. So let's look at the evidence because I think this is actually quite fascinating. First of all you're quite right. We have a lot of evidence that exercise in general is a good thing, a really good thing. When it comes to preventing or slowing down neurodegenerative diseases. Take Parkinson's disease. A 2024 study out of Yale showed that high intensity aerobic exercise could help preserve what are known as dopamine producing neurons. When you develop Parkinson's, you lose those neurons, exercise can help preserve that. That doesn't just slow down the disease, it could actually help the brain repair itself. Now let's talk about distance training specifically. 2020 study out of Sweden, compared the Parkinson's disease risk of long-distance skiers who participated in a big race to the general public's risk. The skiers initially had a close to 30% reduced risk. But over time, that gap narrowed, that benefit became smaller. After 15 years, their risk basically looks similar to everyone else's. So, that suggests that the exercise provides what scientists call a quote. Motor reserve to ward off the disease for a time rather than permanently protecting the brain. So think of that as delaying the onset of a problem as opposed to preventing it completely. We also see the massive benefit of exercise when it comes to Alzheimer's. Recent study out of Hopkins found as little as 35 minutes of moderate exercise per week was linked to a 41% lower risk of dementia. This is really, really inspiring stuff. I mean, if you think about what's happening in the brain, we know we can create new brain cells throughout our lives. And we also know that exercise is one of the things that helps make that happen. It helps create these specific neurotrophic factors, which as one neuroscientist said to me, is kind of like miracle growth for the brain. Now, most of the concern, I think you're talking about stems from something known as ALS, amyotrophic lateral sclerosis, or you may know it as Lou Gehrig's disease. For years, we've seen higher rates of ALS in certain professional athletes, soccer, football players. But even then, researchers note that one risk factor for soccer and football players is that they're taking repetitive hits to the head, right? So studies suggest that for the vast majority of people that's not gonna be the case, and strenuous exercise is not only gonna be safe, but actually beneficial. Now I will say, and this is rare, but for individuals with a specific variant of something known as the CNORF72 gene. I'm gonna repeat that, just in case you wanna write it down. C9ORF 72 gene. And people who have a specific variant of that gene, intense physical stress might, might act as a trigger for ALS. I just wanna throw that out there. It's rare, the research is still emerging, but I think it's important for you to know. The science around this is pretty new, just within the last five years. So we don't know, for example, if other environmental factors may be playing a role here as well. So what's the bottom line, Sahar? I think number one, listen to your body. If you have a family history of motor neuron disease, it might be worth having a deeper conversation with a specialist. Number two, remember that most of the risks, they tend to appear at the extreme ends of human endurance. So don't overdo it. And number three, for the vast majority of us, the cardiovascular benefits, the cognitive benefits of training for a marathon or any kind of exercise for that matter, far outweigh the risks. So I hope that gives you some peace of mind next time you're out on the trail. No need to feel guilty about that runner's high. I'm right there with you. And if you do decide to go for it, Sahar, make sure you follow a training program and add the miles on slowly. I don't want you to be calling back with some question. About a new runner's injury.

'Thanks for all the great questions this week. I love going down the rabbit hole with you. If you have soething on your mind, record a voice memo. Email it to pagingdrgupta@cnn.com or give us a call 4703960832 and leave a message. I'm Dr. Sanjay Gupta, talk to you soon.