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ber of my rides on alpine routes started going down in august of 2022 the number of my rides on another similar route the cañada route started going up as i noted in an earlier post the cañada route is prettier and has less traffic than the alpine routes which is why i switched so why does this matter i found a new route that i liked better than the alpine routes and i switched that s all good right not entirely the current version of the alpine route is 22 miles long and the current version of the alpine cañada route is 33 miles long as compared to the cañada route which is only 17 miles long it is relatively easy to adjust my schedule so that my total weekly mileage is about the same as it used to be what is more difficult is to find longer rides especially rides as long as the 33 mile alpine cañada route two 17 mile long rides on monday and tuesday do not have the same fitness benefits as one 33 mile ride on tuesday and in fact that is the explanation for the reappearance of alpine rides first in september of 2023 and then again in february through october of 2024 my fitness goals at both those times required the longer alpine rides especially the alpine cañada rides the length advantages of the alpine routes are especially important when i am preparing for group metric centuries rides like the art of survival golden hills or ride the rogue in may of 2024 i struggled to keep up during the art of survival and as a result i have recently decided it is time for me to give up group metric centuries without the stimulus of preparing for these rides the need for me to ride the alpine routes is largely gone there is another advantage of the alpine routes and that is the large amount of data i have about my speed over those routes if i am riding one or another of the alpine routes regularly there will be ride to ride variation in my speed that are not meaningful but looking at the pattern of my speed over multiple rides and comparing that to what i was doing in the past gives me a sense if i am getting faster slower or staying the same of course i can do the same thing with my cañada rides but there is less total data and it does not go as far back in time so is less useful given the advantages of doing at least some alpine rides might i ride these routes again in the future absolutely but it is also possible i might not might the fact that i haven t done an alpine ride for nine months suggest that it is more likely i might not maybe but that brings me to one more factor that has reduced my enthusiasm for the alpine routes the least attractive part of these routes is the five to six miles near the start which are on alameda de las pulgas although most of this stretch has a decent bike lane the traffic is somewhat heavy and there is a lot of cross traffic due strip malls that make this stretch uncomfortable and dangerous recently this stretch has been the site of construction by multiple government entities which have made these problems significantly worse that s the bad news the good news is that this construction won t go on forever so i could imagine a time in the future when the construction has been completed i grow nostalgic for these routes and restart riding them at least occasionally posted by zombie cyclist at 9 01 am no comments email this blogthis share to x share to facebook share to pinterest tuesday july 1 2025 the cedar elm loop go to ride three years ago i posted about something i call a go to ride you can read that post to get the whole story but briefly it is a route that i tend to ride over and over again in the picture above i am showing the routes of two go to rides the tamarack sprint on the left side of the picture and the cedar elm loop running diagonally from upper left to lower right corners of the picture both of these routes are loops and a ride consists of multiple laps around that loop typically nine laps for the tamarack sprint and eight laps for the cedar elm loop the tamarack sprint is one mile around with the part i sprint being 0 23 miles and the cedar elm loop is three miles around i posted about the tamarack sprint a while back and i am describing the cedar elm loop in this post for the first time what do these two routes have in common they are located a few blocks from each other they both involve riding the same loop multiple times this the zombie with his 1963 bianchi specialissima at eroica california in 2019 not me the guy holding the bike but the bike itself my 1963 bianchi specialissima i raced this bike as a member of the berkeley wheelmen during the 1970 season rode it from boston to montreal in 1972 and accompanied by my wife agi completed a week long inn to inn bike tour on this bike in 1979 when i restarted cycling 30 years later it was initially on this bike although my specialissima has been largely replaced by more modern bikes for my everyday riding i still love this bike and look for opportunities to ride it what is it about this bike that links it to these two routes sadly it is that it is now impractical for many kinds of rides there are a number of things about it that make it impractical but the one most relevant to this post is that it has sew up tires tires that are glued to the rims tires which i cannot change on the road that means that if i get a flat tire i have to walk my bike home or to where i can get a ride home when i first got my ebike my orbea gain i had a similar problem because of the carbon rims and tubeless ready tires i did not know how to change its tires and so i developed my emerald hills go to ride as a ride where i could walk home from any point on the ride unfortunately this route would not work for my specialissima because of another aspect of its impracticality its lack of low gears because the emerald hills ride is in my neighborhood it is extremely hilly and there is not a snowball s chance in hell that i could complete it on my specialissima that is why i drive to my old neighborhood in san carlos to ride my specialissima before developing the cedar elm loop i rode my specialissima on two routes in san carlos the tamarack sprint and the neighborhood go to rides both of these rides are described in the same post from 2019 what motivated me to develop the cedar elm loop is that i have recently been finding that my body is responding well to long zone 2 rides zone 2 rides are easy low intensity rides although i have gotten better at completing hilly rides while staying within zone 2 that requires low gears or eassist both of which my specialissima lack both the tamarack sprint and the neighborhood routes are too hilly to complete as zone 2 rides on my specialissima therefore to accomplish the two goals of enjoying my delightful specialissima and completing longer rides in zone 2 required finding a flatter route that stayed within walking distance of where i parked my car and the cedar elm loop was that route eight laps around that loop gives me a ride that is 24 miles long and takes me two hours a respectably long ride although i have not yet done so i could generate an even long ride by simply increasing the number of laps doesn t riding around and around the same roads over and over again get boring after all i have said that i find it intolerably boring to ride my trainer for rides longer than 30 minutes in fact i find riding laps outdoors much less boring than riding on my trainer indoors as proof of that back in houston a large fraction of my rides were on the rice track a third of a mile course which meant that even a short ride could involve 35 laps i wouldn t want all of my rides to be on the cedar elm loop but for one ride a week or so the delight at riding my specialissima makes up for a less than exciting route besides the city of san carlos is rather pretty further reducing the potential for boredom posted by zombie cyclist at 9 51 am no comments email this blogthis share to x share to facebook share to pinterest wednesday june 4 2025 does exercise extend lifespan for some time now i have wanted to write a blog post describing the limitations of scientific studies that associate health benefits to exercise i published a gee wiz post back in 2019 describing a study that suggested that subjects in the top 2 3 of fitness were a stunning five time less likely to die in a given year than those in the bottom 25 for purposes of comparison the impact of smoking on annual death rate is a much smaller 1 4 fold in that post i did my best to describe the limitations of that study and alternative explanations for its results but i felt like there was more to say and so i had been collecting facts and ideas to be used in a future blog post what finally got me to write this post was this scientific study does exercise prevent major non communicable diseases and premature mortality a critical review based on results from randomized controlled trials by marcel ballin and peter nordström 09 july 2021 https onlinelibrary wiley com doi 10 1111 joim 13353 the short answer the authors give to the question in their title is no a shocking answer indeed as my son said when i chatted with him about this post that s absurd it flies in the face of decades of research and thousands of other scientific publications he has a point how can ballin and nordström justify such a radical conclusion that exercise does not extend lifespan to explain that requires some background the first thing to point out is that this publication does not contain original data rather it is what is called a meta analysis instead of doing experiments the authors combined the results of multiple published studies an example of that is shown in the figure at the top of this post this figure displays results from twelve published studies on the effect of exercise on either cardiovascular disease e g number of heart attacks and all cause mortality i e how long the subjects of the studies lived let s focus just on all cause mortality for which the authors looked at ten studies in eight of those studies the subjects who exercised lived longer on average than those who did not in one study the subjects who did not exercise lived longer than those who did in one study there was no difference between the two groups however every study has uncertainty and in nine of the studies due to that uncertainty it was not possible to be 95 certain that there was any difference between the two groups further when all ten studies were combined the combined probability indicated that from these ten studies considered together it was not possible to be 95 certain that exercise had any effect on all cause mortality thus the conclusion of the authors of this meta analysis is that there is no statistically significant difference between the longevity of those subjects who exercised and those subjects who did not but what about all the other studies that conclude that exercise does decrease all cause mortality how did none of them end up in this meta analysis to answer that question i have to explain the difference between interventional studies and observational studies the gold standard for scientific studies are randomized interventional studies if you wanted to know if exercise extends lifespan you would enroll a bunch of people in your study randomize them into two groups e g have them flip a coin heads means exercise tails means no exercise have one group follow the exercise program you think will lead to a long life have the other group not do that and then keep track of them for decades until all of them have died you then compare the average lifespans of the two groups there are a lot of obvious problems with this approach what exercise program do you test there is almost an infinite number of possibilities what does it mean not to follow that program supposing a member of the control group enjoys walking around their neighborhood are they forbidden to do that how would you ever get anyone to agree to participate in such an invasive study how would you ever get the review board at your university agree to such an immoral study how would you ever guarantee continuous funding over the long period of this study and what is the general public going to do during the decades of waiting before the last subject dies there are standard workarounds for many of these obvious problems but none of these workarounds are perfect or even close to perfect as a result an alternative approach to answering these questions has arisen the observational study the very beginnings of this field can be traced back to one such observational study done in the mid 1900s by jeremy morris and ralph paffenberger they noticed that bus conductors who walked around the bus during their work day lived longer than the drivers of those buses who sat all the time today such studies are usually based on a questionnaire a list of participants is gathered they are asked to fill out a questionnaire about how much they exercise and then they are followed to see how long they live this shares some of the same problems as the hypothetical interventional study i described above but eliminates many of the most serious problems and thus the vast majority of studies linking exercise to longevity are observational this is important because observational studies have one major disadvantage compared to interventional studies they cannot prove that one thing caused another only that the two are linked in the case of exercise and longevity an observational study can show that exercise is linked to longevity but not that the exercise caused the longevity but what other explanation can there be ballin and nordström would suggest that maybe both exercise and longevity are caused by a common factor inherited good health for example the idea is that a person who is born healthy will feel good and therefore want to exercise they will also live a long time not because they exercised but because of their inherited good health if this contrarian opinion seems implausible to you you can take comfort from the fact that the bulk of the medical community agrees with you that is why my doctor recommends that i exercise and yours probably does too that said this disadvantage of observational studies is why ballin and nordström limited their meta analysis to interventional studies because these studies are randomized they are immune from this alternative explanation if everybody s intuition is correct about the observational studies such studies should be confirmed by the interventional studies and according to ballin and nordström they are not so is that it was all my cycling for health a waste of time not necessarily perhaps it is the interventional studies that are misleading rather than the observational studies those who would criticize the observational approach would use a catch phrase popular in the scientific community correlation does not prove causation that is just because subjects who exercise live longer does not prove that the exercise caused the l...
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