[Music] [Applause] imagine that it's late night you lie in your bed tucked comfortably under your blankets and as you close your eyes and slowly DFT off to sleep your heart travels to someplace far maybe to a tranquil Beach to relax and recover from the previous day this may sound to you like a start of a fairy tale but I assure you sleep as your cardiovascular vacation is not that farfetched off the all and over the past few years I found a passion and I dedicated my research to help unraveling how sleep impacts our cardiovascular health
and today I want to share some Magic ingredients of sleep that contribute to a fantastic cardiovascular vacation each and every night so why are these Min Vacations so important for us well having a healthy heart is actually crucial in achieving healthy longevity as cardiovascular diseases represent the leading cause of death worldwide and even when it's not about long-term Health improving our cardiovascular function can make a difference also in everyday life so recently I've had the brilliant idea to prepare for my first ever half marathon and following common knowledge I Incorporated running to increase my cardiovascular
fitness I also focused on my nutrition to fuel my body with appropriate nutrients and energy and according to an American Heart Association these two factors exercise and nutrition both belong belg to a list of eight key measures that help maintaining and improving our cardiovascular health but wouldn't it be great to also train for a half marathon while sleeping I guess none of you dislike sleep and personally I fell in love with sleep I think sleep is absolutely amazing and luckily last year getting healthy sleep was included to this list of key measures for our cardiovascular
health meaning finally sleep started to get the attention it deserves but evidence was actually out there for a while indicating that both too short but also too long sleep both increased the likelihood of developing medical conditions such as excess body fat elevated the blood pressure or even diabetes and these are all established risk factors for cardiovascular diseases but this evidence it's also based on reducing sleep to one number only to sleep duration and this reflects kind of long- held myth that sleep is a uniform process where our brains are completely shut off and uncoupled from
our bodies a state that Edgar alen po even referred to as those little slices of death but to understand whether our brains are truly silent during sleep we have to visualize brain activity so our brains they're made up of roughly 86 billion little cells the so-called neurons and this immense number is comparable to the number of stars there are in our Milky Way so think of our or think of these neurons as a big Orchestra of instruments where each instrument represents aoup group of neurons and these instruments they can be louder and quieter play faster
and slower rhythms and sometimes each instrument just plays a background Melody whereas during other times a big group of instrument joins to play the main Melody and collectively these instruments generate a complex musical composition that is actually consisting of brain rhythms or also brain waves and for a century we can measure these brain waves by attaching small sensors on the head so this visual representation is possibly not as exciting as listening to a musical Masterpiece at first but it can tell us a lot so you now see a 20- second brain wave trace of a
person having their eyes closed and each line represents here a different location of a sensor placed on the sculp and during this relaxed wakefulness none of the Melodies is visually extremely prominent which is indicated by these random Wiggles on these relatively flat lines but then suddenly during deep sleep thousands of instruments start to play together followed by silence over and over again and this results in brain waves with increased amplitude and a rhythmicity of about one wave per second and we call these waves slow waves and the more instruments that are joining this slow rhythmic
Melody the higher the amplitude of slow waves and the deeper our sleep and this reveals that sleep is definitely not a Merc lies of death but it's actually a highly Dynamic process let's go back now to these slow waves because I think slow waves are are absolutely fantastic because they're true multitaskers so they're for instance involved in cleansing the brain from waste prodin that accumulate during wakefulness though think of slow waves as ocean waves that flush leather that has been thrown into the ocean onto the shore and we also think that slow waves are involved
in promoting our cardiovascular functions so why is that actually the older we turn the fewer slow ways we have and this results in more fragmented and more superficial sleep with aging and given that age is the major risk factor of cardiovascular diseases this AG related decrease in slow waves could represent a strong link between them but still we do not know whether slow WS also directly cause changes in cardiovascular functions but to do so we have to modulate slow waves and about a decade ago researchers found that playing tones during deep sleep enhances these slow
waves actually without even waking people up I mean how amazing is that playing music during sleep can boost the slow waves well it's not actually music but it's rather bursts of noises like this I guess you're now all wondering how this oddly sounding noises can help to enhance deep sleep so let's go back to our Orchestra anology and think of these tones that occur every second which matches the frequency of slow waves as the conductor of our brain Orchestra and the conductor facilitates the synchrony between instruments and again the more instruments that are joining the
slow waves the higher their amplitude and the deeper the sleep so we now applied this soall auditory stimulation to explore the role of these slow waves in promoting our cardiovascular vacation and actually we expect a deep sleep to resemble a true relaxing at the beach vacation which is marked by low cardiovascular activity meaning low heart rate and low blood pressure and generally across deep sleep we found this level of cardiovascular relaxation but surprisingly when these tones were played and slow ways were enhanced we found a cardiovascular activation meaning a short increase in heart rate and
short increase in blood pressure but just for a few seconds and this is kind of a dynamic response of our cardiovascular system to this enhance slow waves and we're now going to term these response cardiovascular pulsations and interestingly these pulsations also occur naturally during very specific moments of your deep sleep but by enhancing slow waves we can make this pulsations occur more frequently we think or this expert CHS that slow waves are truly important during sleep but are these pulsations then really beneficials for our hearts so our hearts they beat around 100,000 times a day
and during each cardiac cycle the heart contracts to eject blood to the body's arteries and relaxes again to get filled up with new blood and after just one night of Boo boosting slow waves we found the hearts of our participants to contract more strongly but it also increased the ability of the heart to relax and get filled up with new blood and both together this contraction and relaxation indicate improved heart function so this results show that one magic ingredient of sleep that promotes our nightly card of asav vacations are indeed slow waves so when we
fall into deep sleep our hearts indeed travel someplace far but this cardiovascular vacation is possibly not just pure relaxation but also involves some active Parts it is as if our hearts are not just exclusively sunbathing but also serving a bit in the ocean and these active Parts these cardiovascular pulsations likely promote our cardiovascular function and health during sleep so remember slow waves as ocean waves that flow slitter onto the shore these pulsations could actually represent stronger and more frequently occurring waves that more effectively flush the litter onto the shore and this could be even involved
in Pro processes in the brain that are actually involved in Alzheimer's disease so we believe that slow wave stimulation could be used in the future as a complementary method to treat cardiovascular diseases or even Alzheimer's disease and we also think it could be used in preventative medicines and sports to enhance cardiac function or even facilitate recovery and maybe if I used this technology myself I would have run my half Merin faster if only I listened to my own research I guess many of you are now wondering where you can download this app that place this
tones that to enhance your slow waves and enhance your cardiovascular vacation well unfortunately it's not that simple as these tones have to be played during the right times during deep sleep to avoid sleep disruption and simply down loing an app or even coupling it with sleep trackers such as smart watches will not provide this necessary information and additionally most Studies have been conducted in sleep Labs also hours and if you now think that participating in a sleep study is similar to spending a night in a hotel well this is Far From Reality this was one
of our participants equipped with all these sensors and cables to literally Rec tons of vitals and you know in the end we just ask them to sleep as normally as possible so we cannot transfer this specific setup directly to your homes and unfortunately we're also facing some challenges such as audit auditory stimulation loses its efficiency with aging it is as if our Orchestra loses its ability to synchronize to external conductor but we are currently tackling these challenges by developing portable but also comfortable Solutions with additional stimulation methods to increase slow waves and your cardiovascular vacation
across the aging process and while we're giving our best to develop such devices I want to leave you with five science back hacks to increase deep sleep avoid coffeine to close opposed to bedtime as it can actually reduce time spent in deep Sleep If consumed up to 8 hours before going to bed limit alcohol consumption as it is a big myth that alcohol guarantees a good night's sleep it actually interferes with sleep during later Parts makes it more superficial and more fragmented reduce daytime napping essentially if you have problems with your nighttime sleep so long
naps where you even enter deep sleep can disrupt your sleep Skittle make it harder to fall asleep and also reduce time spent in deep Sleep on the next night then engaging in regular daytime exercise can actually greatly improve deep sleep but try to avoid high-intensity workouts to close to bedtime as induced rise in your body core temperature can make it harder for you to end the Deep Sleep keep keeping your hands and feet warm can actually facilitate this needed drop in your body core temperature to make you fall asleep more quickly and it can also
prolong time spent in deep sleep so I want to hear highlight that sleep is a very individual process and not every method may work for everyone but what all of us can do is to prioritize sleep in our lives as it is our bod's Min vacation such as you take vacation to relax and recharge from work your heart also needs and deserves the vacation that deep sleep provides so I'd like you to remember slow waves during deep sleep as your active cardiovascular vacation and as I'd like to say sleep represents the most powerful recovery system
that we have thank you
