Kudos to you for taking control of your research content on UA-cam instead of just giving interviews to other channels. I appreciate your expertise and knowledge.
We're living in an era where the sum of human knowledge is literally at our fingertips, a concept that would have seemed like pure science fiction to our grandparents. The sheer scale of detail and clarity presented here is nothing short of revolutionary. It's a profound reminder of the incredible age we inhabit, where learning and growth are boundless, and the mysteries of the world are unraveling right before our eyes. What a time to be alive indeed! To think that just a generation or two ago, such knowledge was confined to the walls of elite institutions or simply didn’t exist. Now, it's shared freely, allowing anyone with curiosity and an internet connection to explore the wonders of our world and beyond. This video is a testament to human progress and the democratization of knowledge. Thank you
I’ve watched every video I can find of this metabolic genius, since his first interview with Peter Attia years ago. His knowledge has completely reversed my metabolic syndrome.
I absolutely love this man . The amount of info he gives .. is just out of this world .. In other fields .. people will have to pay to get this, he gives it for free,to multiple UA-camrs as well and the clarification is 100% I'll never forget him even when I become a good runner 💯
Huge fan Dr. San Milan. I took your Zone 2 training to heart in October 2022 after changing my diet to chicken and fish in August 2022 on the advice of my physician. He was stuned in January 2023 when my cholesterol had dropped to 122 from 188 and my HDL, which I could never get above 38, jumped to 48. All this without increasing miles or hours exercising (I do 3x2.5 hours/week). My physician stated that he hadn't seen these kind of results with high dose statins. I would love to hear you talk about how these came about by the Zone 2 exercise adaptations by implementing your exercise recomendations. Also interested in future videos on the intersection of metabolic health/deficiencies and ilnesses. Very happy that you started your own channel!!!
Thank you for sharing your years of experience and expertise with us. You've taken complex material and made it understandable and applicable to our training. As a multi-year amateur triathlete and someone who just survived cancer i've found learning from you invaluable this past year. God bless you :)
Thank you Inigo for your expertise and sharing it with us all over for free. Please continue to share knowing it improves our world(and ignore any critiques about visual clarity-you are giving this to us free -no complaints from viewers please)
¡Íñigo, mi más sincero agradecimiento por todas sus participaciones y por hacernos entender sus descubrimientos! Le llevo siguiendo desde hace poco, pero sus explicaciones rigurosas, exactas, claras y sencillas me hacen entender por qué la Zona 2 es tan importante. Acostumbrado a ver a divulgadores, que hacen muy bien su labor, siempre echo de menos que me explique los conceptos y entrenamientos el mismo científico que lo está investigando. Muchas gracias, Íñigo, le deseo lo mejor en esta nueva aventura de UA-cam.
I think why this video is so helpful is because the insights can be applied to all levels of performance - whether professional or whether those of a much lower standard of fitness are simply looking to improve their metabolic health as they age. Thank you.
Thank you for sharing. I still remember my first time working with you as a young rider expecting you to tell me what to do but instead and I got a teacher educating me on why we do what we do. Amazing work!!
Thank you Dr San Milán for your time and for your research. As others have stated, you have been very generous in sharing your research and its practical implications. Now, let’s hope Tadej is able to use it to win the double this year!
Terrific video! I've watched all of the videos you've appeared in, but the inclusion of an actual graph really takes this to the next level. What would really be helpful is if you were to attach a PDF of the graph to the show notes, so we could download and have it as a reference. Look forward to your next post
A few years back, I stumbled upon your podcast with Peter Attia. What I learned from you changed my life. No, I am not overselling it. It literally changed my life, as my life revolves around mountain trail running. After applying a 'zone 2 training philosophy' to my day to day training, I went from being a very mediocre athlete to a front pack (but far from elite) age group runner. When people ask me how the heck I can run at 10k-14k ft while negotiating steep, technical terrain at zone 2-3 heart rate (using a 5 zone model) I simply refer them to that 'The Drive' episode. Thank you for what you do, Sir.
Oh wow from the horses mouth! Excited to watch. Due to you and MAF method all I do is easy/zone 2 (have a few health issues, so don't like to turn on the stress response with intervals). Has made a big difference to my health!
Great presentation, well done. Its also clear that Lydiard knew through testing himself in the 50s that Steady Aerobic paces/intensitys around 80% av.hr of L.T (1/4 effort) stimulated the slow twitch fibres the best for the 10-12wk base phase of a training pyramid. Coined Marathon Conditioning. Alot of modern athletes dont understand the why, but this video is great for explaining it. Lactate needs to be metabolised as best as possible and racing say a 10k is producing a ton of acid. In shorter races particularly 800m. Its why New Zealands famous Sir Peter Snell was able to kick so hard in the final lap and break the w.r half and full mile 60yrs ago. 1:44.3 still an incredible time 60yrs later is epic. His 1030miles ran in the 10wks + 400miles jogging layed a massive base to tolerate extreme acidisis in the 800m & 1609m. Cheers 🎉
Very very happy to see you here and opening that window even more. I did some diagnostics lately and I guess I understood a lot already about the metabolics, but this is very helpful indeed! - And all definitions of zones aside: What an amazing machinery our body is!!! 😄
Wow, what a great video and great explanation of the training zones. I have read so many articles about them and was still not clear. You explained it very well and has helped me understand it. Thank you
Esto sí que es un auténtico regalo de Navidad. Todo lo mejor Iñigo para este año y muchísimas gracias por tu labor, tu capacidad única de divulgación y el entusiasmo que consigues despertar con tu talante en los que llegamos a esto desde el lado "profano". Un abrazo!!
Thank you Dr. San Millan! I have watched so many of your interviews on GCN and other platforms. It is great to get it straight from you. Thank you so much for creating your own channel.
This was amazing! Now that I understand zone2 a lot better I would love to see another video explaining the intricacies of it, like, why it's necessary to stay in the zone for long durations, whether you can or can't do a hard effort before or after Z2, do the different energy systems stay activated after you've exited the zone ... and so forth.
Great Content! It would be great to get your opinion for runners on how the Norwegian Double Threshold as practiced by the Ingebrigtsen' brothers, fits with your training philosophy. They seem to be doing 2 or 3 double training days at LT2, (4 or 5 sessions) and one session day hill sprints zone 5/6, per week. How do they have their LT1 so far to the right...maybe all their easy session are at LT1, with high volume? would be great to hear your thoughts. Thank you. (Leif Inge Tjelta has a few good papers)
If you look at the Marius Bakken site it suggests the Norwegian method has the majority of these double thresholds 0.3-0.5 below the LT2 . With the first session of the day below the second session of the day which is itself below LT2. They use the hill intervals to run higher than LT2
👏 👏 👏 Bravo Dr Iñigo. Mucho, mucho más claro escuchar su explicación que las que tratan de articular otros cuando lo invitan a un podcast. Me atrevo a sugerir como próximo tema un repaso de los ciclos de Producción de Lactate y de Oxidación de Lactate, digamos regresar a la base bioquímica de ambos ciclos para poder entender mejor la dinámica metabólica. Mil gracias.
Amazing, thank you for creating this channel, your explanations and knowledge transmission are the best one can find. Gracias por el esfuerzo de sacar tiempo de donde no lo hay para crear estos vídeos.
Great presentation. There are tons of concepts here, perfectly explained and made easily understandable. Thank you so much Doctor, for sharing your experience with us !
Dr. San Millan: The metabolic map chart really isn't big enough to see in the video. You might want to post a link where people can download it. Cheers.
Thank you. I have been trying to explain how we determine heart zones when we do metabolism testing as well because people are getting confused about heart zoning, zone 2 and personalization.
Dear Mr. San Milán, thank you very much for this detailed zone definition. You mentioned the benefits of zone 2 and zone 4 training, but is there any benefit of spending time in the "transition stage" zone 3 compared to zone 2?
You have to train zone 3 before zone 4. You have to train the first or "weakest" fast twitch muscle fibres and increase MCT 4 and MCT 1, and then increase the intensity to recruit the next level or "stronger" fast twitch muscle fibres.
Great Explanation. Thank you so much. Are you planning continuing this subject with more videos? It would great to hear from you how shall we then apply this zones into our training, ie. what sort of ratio should we see of this zones within our weekly volume for example depending on the time of season, etc? ❤❤❤
Thank you very much. Just to be clear, at about 13:13 you meant to say zone 4 (not zone 2), correct? I'm not a competitive athlete, just a 52 yr old trying to take care of myself. But this info is all new and it's all fascinating. Very helpful and inspiring.
Yeah he made a bit of an error there. Definitely meant to say Zone 4. These athletes also tend to do Zone 5 work to a lesser extent to sharpen up for races.
Thank you very much for sharing the knowledge based on the long years effort ... It is very clear the basis of zone classification... and it is help me very much to implement in my daily own training ❤🙏
@inigosanmillan1Happy New Year Dr. Millán. Thank you so much for this video. Hugely helpful! It would be great if you could share your slide page 13 in better quality, perhaps PDF. And don't hestiate sharing the other slides, too. ;-) Thanks again.
Thank you @inigo for doing this!! I’ve heard you on Petter Attias podcast and love your athletes in cycling. I look forward to more videos from you. This is excellent!!!
Would love to know your view on use of exogenous ketones - as a fuel source and whether exogenous ketones change relative system use beyond their effect on substrate inputs. Second given increasing use of GLP-1 whether these medicines have any metabolic effects beyond those related to relative fasted vs fed state. Thank you for the concise review.
Hi, great video! Can you show a workout schedule to from one of your top guys with a detailed explanation about why and how regarding the volume, zones, intervals,... Thanks!
The science Ive seen says we don't "switch" to the fast twitch fibers, what happens is we recruit more and more fibers as the intensity goes up (we send more and more signals to the faster fibers if we have them) You dont stop using slower twitch fibers when you run faster. We also have to train the nervous system, AND as we get older we dont even keep making fast twitch muscles as we replace the old cell because we dont have the stem cells for the fast twitch fibers so fast twitch get replaced by slower twitch muscle fiber. We can slow the process but we cannot stop it.
Great video, thanks Doc! I think a good follow up would be tips to understand or define easily how one understands in which zone (s)he is in during exercise. Eg. heart rate or speed or power etc.
Kudos to you for taking control of your research content on UA-cam instead of just giving interviews to other channels. I appreciate your expertise and knowledge.
We're living in an era where the sum of human knowledge is literally at our fingertips, a concept that would have seemed like pure science fiction to our grandparents. The sheer scale of detail and clarity presented here is nothing short of revolutionary. It's a profound reminder of the incredible age we inhabit, where learning and growth are boundless, and the mysteries of the world are unraveling right before our eyes. What a time to be alive indeed! To think that just a generation or two ago, such knowledge was confined to the walls of elite institutions or simply didn’t exist. Now, it's shared freely, allowing anyone with curiosity and an internet connection to explore the wonders of our world and beyond. This video is a testament to human progress and the democratization of knowledge. Thank you
Very well said.
Thank you, so nice just to listen to your explanation without an interviewer stopping you constantly to interject their own ideas.
So, so glad you decided to start your own channel. Thank you for sharing your knowledge with the rest of us.
I’ve watched every video I can find of this metabolic genius, since his first interview with Peter Attia years ago. His knowledge has completely reversed my metabolic syndrome.
Inigo, finally we have chance to listen and follow your lessons. Thank you!
I absolutely love this man .
The amount of info he gives .. is just out of this world ..
In other fields .. people will have to pay to get this, he gives it for free,to multiple UA-camrs as well and the clarification is 100%
I'll never forget him even when I become a good runner 💯
The one video to rule them all! Fuel source, muscle fibre use, lactate level and zones. Thank you for bringing it all together so concisely.
Huge fan Dr. San Milan. I took your Zone 2 training to heart in October 2022 after changing my diet to chicken and fish in August 2022 on the advice of my physician. He was stuned in January 2023 when my cholesterol had dropped to 122 from 188 and my HDL, which I could never get above 38, jumped to 48. All this without increasing miles or hours exercising (I do 3x2.5 hours/week). My physician stated that he hadn't seen these kind of results with high dose statins. I would love to hear you talk about how these came about by the Zone 2 exercise adaptations by implementing your exercise recomendations. Also interested in future videos on the intersection of metabolic health/deficiencies and ilnesses. Very happy that you started your own channel!!!
Pure MASTERCLASS!!!!!! Thank you for your hard work, sir.
Concise but also detailed. Clear and easy to understand. Incredible lecture.
Excited to expand my understanding of training zones from the master himself.
Absolutely fantastic video.
In 15 minutes you’ve made weeks of Instagram content obsolete.
Looking forward to more of your videos
Outstanding video! Concise knowledge in just about 15 minutes, and starting point for those ready to educate themselves further.
Thank you for sharing your years of experience and expertise with us. You've taken complex material and made it understandable and applicable to our training. As a multi-year amateur triathlete and someone who just survived cancer i've found learning from you invaluable this past year. God bless you :)
Incredibly well explained and easy to follow even for non native English speakers. Thanks for putting out some great, unagitated and helpful content!
Thank you Inigo for your expertise and sharing it with us all over for free. Please continue to share knowing it improves our world(and ignore any critiques about visual clarity-you are giving this to us free -no complaints from viewers please)
¡Íñigo, mi más sincero agradecimiento por todas sus participaciones y por hacernos entender sus descubrimientos! Le llevo siguiendo desde hace poco, pero sus explicaciones rigurosas, exactas, claras y sencillas me hacen entender por qué la Zona 2 es tan importante.
Acostumbrado a ver a divulgadores, que hacen muy bien su labor, siempre echo de menos que me explique los conceptos y entrenamientos el mismo científico que lo está investigando. Muchas gracias, Íñigo, le deseo lo mejor en esta nueva aventura de UA-cam.
I think why this video is so helpful is because the insights can be applied to all levels of performance - whether professional or whether those of a much lower standard of fitness are simply looking to improve their metabolic health as they age. Thank you.
Thank you for sharing. I still remember my first time working with you as a young rider expecting you to tell me what to do but instead and I got a teacher educating me on why we do what we do. Amazing work!!
Thank you Dr San Milán for your time and for your research. As others have stated, you have been very generous in sharing your research and its practical implications. Now, let’s hope Tadej is able to use it to win the double this year!
Terrific video! I've watched all of the videos you've appeared in, but the inclusion of an actual graph really takes this to the next level. What would really be helpful is if you were to attach a PDF of the graph to the show notes, so we could download and have it as a reference. Look forward to your next post
A few years back, I stumbled upon your podcast with Peter Attia. What I learned from you changed my life. No, I am not overselling it. It literally changed my life, as my life revolves around mountain trail running. After applying a 'zone 2 training philosophy' to my day to day training, I went from being a very mediocre athlete to a front pack (but far from elite) age group runner. When people ask me how the heck I can run at 10k-14k ft while negotiating steep, technical terrain at zone 2-3 heart rate (using a 5 zone model) I simply refer them to that 'The Drive' episode. Thank you for what you do, Sir.
Oh wow from the horses mouth! Excited to watch. Due to you and MAF method all I do is easy/zone 2 (have a few health issues, so don't like to turn on the stress response with intervals). Has made a big difference to my health!
Great presentation, well done. Its also clear that Lydiard knew through testing himself in the 50s that Steady Aerobic paces/intensitys around 80% av.hr of L.T (1/4 effort) stimulated the slow twitch fibres the best for the 10-12wk base phase of a training pyramid. Coined Marathon Conditioning. Alot of modern athletes dont understand the why, but this video is great for explaining it. Lactate needs to be metabolised as best as possible and racing say a 10k is producing a ton of acid. In shorter races particularly 800m. Its why New Zealands famous Sir Peter Snell was able to kick so hard in the final lap and break the w.r half and full mile 60yrs ago. 1:44.3 still an incredible time 60yrs later is epic.
His 1030miles ran in the 10wks + 400miles jogging layed a massive base to tolerate extreme acidisis in the 800m & 1609m. Cheers 🎉
So cool that you have your own channel now. Love how you share all your knowledge.
This was great and I hope you do more in the future. It's always good to hear from the person who's done the research.
can we get a download for the metabolic map please
Also the other pop up background slides too as they are not too low definition.
I think it's on his insta
+1
@@brochslowcoach
Hi, did you find diagrams?
I was able to zoom in on the slide while the video was playing on my phone and screen shot it. It was good quality. Hope this helps 👍
Thank you. So good to hear directly from “The Master”. Looking forward to a lot more content
Very very happy to see you here and opening that window even more. I did some diagnostics lately and I guess I understood a lot already about the metabolics, but this is very helpful indeed! - And all definitions of zones aside: What an amazing machinery our body is!!! 😄
This is so valuable. I can not thank you enough, Dr.
Wow, what a great video and great explanation of the training zones. I have read so many articles about them and was still not clear. You explained it very well and has helped me understand it. Thank you
Thank you Iñigo for sharing your incredible knowledge and expertise with us! Looking forward to new content :)
Thanks for producing this content Doc, Best wishes to you and the show.
Esto sí que es un auténtico regalo de Navidad. Todo lo mejor Iñigo para este año y muchísimas gracias por tu labor, tu capacidad única de divulgación y el entusiasmo que consigues despertar con tu talante en los que llegamos a esto desde el lado "profano". Un abrazo!!
Thank you Dr. San Millan! I have watched so many of your interviews on GCN and other platforms. It is great to get it straight from you. Thank you so much for creating your own channel.
Thank you for sharing wealth of knowledge for anyone really wanting to learn their training zones. 🙏💪
Many thanks for the compact definition of your training zones.
Many thanks for the clear explanation. Looking forward to your next posts!
Thank you for sharing this information built on decades of practical scientific work. Inspiring and life changing.
Thank you for sharing both your knowledge and your point of view!
I'm looking forward to your videos to learn more about endurance training!
I would love a Dr Inigo San Millan diet video - his recommendations for how to fuel this approach
Great explanation! I’m glad you have created your own video on this. I have been listening to you on many podcasts about the same info.
Very interesting presentation and thanks for sharing. Next you could discuss how to increase lactate threshold.
Thank you Dr Inigo San Millan. I'm going to train at 125 to 130 bpm from now on with high intensity at the end of the workout
Great! Hopefully this is the first of many. Thanks so much Dr Iñigo.
Great content Professor. Keep publishing whenever you can/want.
Brilliant Inigo! Great to see you have your own channel
Very informative Iñigo! Looking forward to the next!
Incredible, it's crazy how yo give give such amount of information in 15 minutes. So inspiring
Thank you Inigo,
I hope more videos will follow.
Please explain and show more practical examples to make us understand clearly.
This was amazing! Now that I understand zone2 a lot better I would love to see another video explaining the intricacies of it, like, why it's necessary to stay in the zone for long durations, whether you can or can't do a hard effort before or after Z2, do the different energy systems stay activated after you've exited the zone ... and so forth.
Great Content! It would be great to get your opinion for runners on how the Norwegian Double Threshold as practiced by the Ingebrigtsen' brothers, fits with your training philosophy. They seem to be doing 2 or 3 double training days at LT2, (4 or 5 sessions) and one session day hill sprints zone 5/6, per week. How do they have their LT1 so far to the right...maybe all their easy session are at LT1, with high volume? would be great to hear your thoughts. Thank you. (Leif Inge Tjelta has a few good papers)
You ask the right question :-). I would only argue they are below LT2 not at.
If you look at the Marius Bakken site it suggests the Norwegian method has the majority of these double thresholds 0.3-0.5 below the LT2 . With the first session of the day below the second session of the day which is itself below LT2. They use the hill intervals to run higher than LT2
Thanks so much Inigo, great video. Looking forward to more when you have the time. Happy New Year.
👏 👏 👏 Bravo Dr Iñigo. Mucho, mucho más claro escuchar su explicación que las que tratan de articular otros cuando lo invitan a un podcast. Me atrevo a sugerir como próximo tema un repaso de los ciclos de Producción de Lactate y de Oxidación de Lactate, digamos regresar a la base bioquímica de ambos ciclos para poder entender mejor la dinámica metabólica. Mil gracias.
Thank you Sir for taking time to share your knowledge with us!
Amazing, thank you for creating this channel, your explanations and knowledge transmission are the best one can find. Gracias por el esfuerzo de sacar tiempo de donde no lo hay para crear estos vídeos.
Great presentation. There are tons of concepts here, perfectly explained and made easily understandable. Thank you so much Doctor, for sharing your experience with us !
Dr. San Millan: The metabolic map chart really isn't big enough to see in the video. You might want to post a link where people can download it. Cheers.
Yes please. Please post link to metabolic map.
Thank you. I have been trying to explain how we determine heart zones when we do metabolism testing as well because people are getting confused about heart zoning, zone 2 and personalization.
Dear Mr. San Milán, thank you very much for this detailed zone definition.
You mentioned the benefits of zone 2 and zone 4 training, but is there any benefit of spending time in the "transition stage" zone 3 compared to zone 2?
You have to train zone 3 before zone 4. You have to train the first or "weakest" fast twitch muscle fibres and increase MCT 4 and MCT 1, and then increase the intensity to recruit the next level or "stronger" fast twitch muscle fibres.
Welcome! Great to see you here.
Great Explanation. Thank you so much. Are you planning continuing this subject with more videos? It would great to hear from you how shall we then apply this zones into our training, ie. what sort of ratio should we see of this zones within our weekly volume for example depending on the time of season, etc? ❤❤❤
I love listening to your explanations of these concepts. It's extremely helpful for me.
Huge fan of Dr. Inigo!
This is probably the most needed video in the space. Thank you so much!
please do more videos!! :D it's pure technician knowledge we need!
Thank you! Great explanation. The timing (31 Dec) is GREAT for the "more exercise" New Year's Resolution.
Thank you very much.
Just to be clear, at about 13:13 you meant to say zone 4 (not zone 2), correct? I'm not a competitive athlete, just a 52 yr old trying to take care of myself. But this info is all new and it's all fascinating. Very helpful and inspiring.
Yeah he made a bit of an error there. Definitely meant to say Zone 4. These athletes also tend to do Zone 5 work to a lesser extent to sharpen up for races.
Fantastic news that you have your own channel! Liked, commented and subscribed!
Thank you very much for sharing the knowledge based on the long years effort ... It is very clear the basis of zone classification... and it is help me very much to implement in my daily own training ❤🙏
Thanks a lot for opening this specific channel, look forward to see other videos... By the way even interviews with Peter Attia are fantastic !
Dr Inigo el mejor. Gracias por el video.
Perhaps a future discussion could cover transition from carbohydrate to fat metabolism in endurance athletes as they deplete carbohydrate reserves.
Thanks so much! Really excellent explanation here. Thanks so much, Dr San Milan.
@inigosanmillan1Happy New Year Dr. Millán. Thank you so much for this video. Hugely helpful! It would be great if you could share your slide page 13 in better quality, perhaps PDF. And don't hestiate sharing the other slides, too. ;-) Thanks again.
Where can I find a copy of Dr. San Millan's The Metabolic Map?
Brilliant presentation 💯 -understandable, smart, and useful for a long healthy life. ❤💪. Grateful for your passion and scientific work, my friend. 🙏🫶
You’re the best! Thanks for sharing it in such an easy way
Thankyou so much Inigo. Clear and concise. Best video I have seen describing the physiology of training zones. Keep up the great work. 😀🚴♂️🏃🇦🇺
Thank you so much for the informative content. Really looking forward to seeing more of this 🙏🏼
This is gold...please keep up the good work...
A very good and clear survey on this subject, thanks a lot for this video 🙏
thank you so much for sharing your research about Zone 2 training, Mitochondria function and so on, for sure this is quite useful for everybody.
Thank you @inigo for doing this!! I’ve heard you on Petter Attias podcast and love your athletes in cycling. I look forward to more videos from you. This is excellent!!!
Ińigo, thank you so much for posting this!! Super educational useful. I look forward to more posts from you!!
Very generous with your time - thank you 🍷
Please do not stop with your video go we appreciate you a lot
Thx for breaking down current science for everyone and sharing!
Thank you Dr. Inigo, very insightful. It would be great to hear from you on how to clear lactate in the race settings?
WOW!!!Thank you so much! So grateful to have this information!!! Amazing insights!!!!
I wish I could get that diagram from that presentation. I tried to zoom in the best I could but alas...
Would love to know your view on use of exogenous ketones - as a fuel source and whether exogenous ketones change relative system use beyond their effect on substrate inputs. Second given increasing use of GLP-1 whether these medicines have any metabolic effects beyond those related to relative fasted vs fed state. Thank you for the concise review.
Terrific. The definition of zone 2 as maximum absolute fat burning rate is nice and simple.
Hi, great video! Can you show a workout schedule to from one of your top guys with a detailed explanation about why and how regarding the volume, zones, intervals,... Thanks!
Inigo!!! love you started this! Gracias!!!
Explicación genial. Muchas gracias por el video. Deseo que sea el primero de muchos
The science Ive seen says we don't "switch" to the fast twitch fibers, what happens is we recruit more and more fibers as the intensity goes up (we send more and more signals to the faster fibers if we have them) You dont stop using slower twitch fibers when you run faster. We also have to train the nervous system, AND as we get older we dont even keep making fast twitch muscles as we replace the old cell because we dont have the stem cells for the fast twitch fibers so fast twitch get replaced by slower twitch muscle fiber. We can slow the process but we cannot stop it.
Muchas gracias por su investigación y su divulgación!
Great video, thanks Doc! I think a good follow up would be tips to understand or define easily how one understands in which zone (s)he is in during exercise. Eg. heart rate or speed or power etc.