The third installment of BRAINSLEEP LIFE features Shinsuke Yamanaka, the 29th-generation WBA Bantamweight World Champion, who holds the record for 12 world title defenses (2nd highest in Japanese boxing history) and is currently active on YouTube.
Q: Please introduce yourself.
A: I'm Shinsuke Yamanaka, the 29th-generation World Bantamweight Boxing Champion.
Q: What motivated you to start boxing?
A: I was a baseball player originally, but when I was in junior high school, I saw a world boxing match on TV, and the championship belt worn by the winner looked incredibly shiny. That's when I decided I wanted to start boxing when I entered high school and get a championship belt myself.
I wrote in my junior high school graduation album that my dream was to become a WBC world champion, so when I actually became a WBC world champion about 15 years later and my dream came true, I honestly couldn't believe it.
Q: Can you tell us about your daily schedule when you were an active boxer?
A: I typically woke up around 7:00 AM and went for a road run. I'd run 5 to 10 km depending on how I felt that day. After the run, I'd have a combined breakfast and lunch, then head to the gym from 3:30 PM to around 6:00 PM. After my gym workout, I'd go home, eat dinner, and then I was usually in bed by 10:00 PM.
Q: When you were an active boxer, was there anything you paid particular attention to regarding sleep?
A: I made sure to get enough sleep, and I never really had insufficient sleep.
However, what I found challenging was that if I slept a little more because I hadn't had enough, my performance often suffered. Napping between morning practice and the evening gym session was very important, but I did find that oversleeping could make me less active.
When I was active, there was guidance on physical training and nutrition, including supplements, but absolutely no guidance on sleep. It might have been different if there were coaches who focused on that.
Q: Did you have any sleep-related concerns even after retiring?
A: I often stay in hotels for business trips, and I frequently find that the pillows and mattresses aren't a good fit. Many mattresses are quite soft, aren't they? It was the same when I was active; I didn't really get along with overly soft mattresses, so I'd feel a bit sluggish the next day. As for pillows, I preferred something a bit firmer and higher than fluffy ones, so I notice this even more now that I travel a lot.
Also, regarding pillows, my head would get hot and I'd wake up because of the trapped heat.
Q: Can you tell us if you've noticed any changes in your sleep since using BrainSleep products?
A: Since I started using BrainSleep products, I've been able to start my mornings feeling truly refreshed. I'm not an active athlete anymore, but I jog 3-4 times a week. Even before I start jogging, I feel incredibly light and refreshed. I'm definitely lighter than before I started using BrainSleep products.
As for the pillow, the way it dissipates heat is completely different. My head getting hot and waking me up due to trapped heat happened in hotels, and sometimes at home when my kids would take my pillow, so I really feel the difference there.
I often feel like I've had a good night's sleep, a deep sleep, when I wake up in the morning. Even just sleeping on BrainSleep for a day after returning from a business trip, I definitely feel a difference.
Q: If there's anything you particularly like about using BrainSleep products, please tell us.
A: When I was an active boxer, I was particular about the height and firmness of my pillow. There are three types of height: Standard, Low, and High, and I really like using the High one. Also, the firmness of the BrainSleep Pillow is very much to my liking.
Also, I was shocked because I never imagined being able to wash a pillow. You can remove and wash the covers, but I didn't know about products where you could wash the entire inside, and I used to think pillows were a bit dirty, you know? Apparently, we sweat a lot, and it's something we use every day, so it gets really dirty. So, being able to wash the entire pillow is truly wonderful, and you can wash it and dry it on the same day to use it again, which is really great.
When I tried the BrainSleep Comforter, I thought it might be too heavy when I picked it up. But when I actually slept with it, it had a moderate weight that felt reassuring. The top part is the heaviest, but there are also weights on both sides so it doesn't get pulled up, so I'm able to stay covered until morning.
Q: We hear your family also uses BrainSleep. Has their life changed?
A: Everyone in my family is doing well because they can all sleep on BrainSleep mattresses now. I can also keep up with my energetic kids and play with them properly, so that might be thanks to BrainSleep. My wife recently started complaining of neck pain, and a pillow is scheduled to arrive at our home soon, so I hope her neck will improve after sleeping on it.
Q: Besides your family, is there anyone else you'd like to see experience BrainSleep?
A: I want all athletes, including professional boxers, to use it.
When I was an active boxer, I trained hard every day, so when I slept on this product, I thought, "I wish I could have used BrainSleep when I was active." There were days during my active career when I was tired no matter how much I slept, so I believe using BrainSleep would have definitely made my body feel better.
What we really needed to consider was sleep quality. I want future athletes to embrace sleep quality, not just quantity.
Q: You mentioned that your awareness of sleep quality has increased. Do you have any thoughts on what you'd like to challenge yourself with in the future?
A: I truly believe that improved sleep quality leads to enhanced performance, so I want to work together to promote and engage in activities that raise the quality of sleep in Japanese sports.





