Bone mass/arterial degredation after PCT

[Mark L]

“Case studies in physiology: Impact of a long‐distance hike on the Pacific Crest Trail on arterial function and body composition in a highly fit young male”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7931801/

Significant spine and pelvis bone mass loss as well as deterioration of arterial health in an extremely fit young male after completing the PCT. Speculative cause is typical hiker diet in combination with high exertion. Expectation was opposite: that lengthy weight bearing would increase bone mass.

The study limitations are enumerated. I would like to see others, and would love to know how much of this could be mitigated or prevented with more effort toward a healthier diet and a slower pace.

Even so, given the subjects age and fitness level and daily regime of adding so many pushups, I find this concerning. I realize that a great many older people complete long trails each year, and one has often been an aspiration for me. But my greater aspiration by far is doing what is best for my overall health as the years speed by.

Mark

 

[Murali C]

I have read that Tour de France athletes also suffer from bone loss after their 2000+ mile race.

PCT is also a pretty gruelling hike and I suspect lots of sweating where you lose lots of minerals. Being young, I doubt he took any multi-vitamins etc  Though it will be interesting to test again after a few years to see if this was a temporary or permanent effect.

I used to bicycle a lot – close to 3000+ miles a year for lots of years here in hot Austin, TX  – and I have thyroid imbalances as well. I was diagnosed with Oteoporosis with a bone density test in my mid 40’s. No symptoms – just a routine test. I have been taking Calcium/multi-vitamins ever since – haven’t retaken a bone density test.  Need to do that. Since cycling is low impact exercise, I switched to backpacking and exercising with a backpack 12 months a year. Again no symptoms of low bone density or osteoporosis etc.

[Bonzo]

“Hiker diet” covered a lot of the causative bases, there.  So many people focus on the most caloric density per ounce/gram, without thinking about nutritional density and breadth; sometimes it seems that even paying attention to the basic macronutrients goes by the wayside in the search for lighter food sacks.  I’ve done the same thing, and the result wasn’t pretty: complete bonks right in the middle of hikes…so, I’m not surprised to see wasting taking place.  The best advice I got on the subject was from my doctor: in her words, “I want you to eat as much as you legitimately need, and I want you to have the most varied diet that you can stand.”  That, and a better understanding of nutrition, have helped me avoid the health complications inherent to pushing oneself.

Also, good timing: I was vaguely considering a PCT this next year. 🤔

[DWR D]

Like any machine, the body needs rest and maintenance periods.

Every 3 or 4 days, I like a zero day… totally zero… sit in camp, read, eat. The next day I feel rejuvenated… legs strong again, and more fun.

Just because you CAN do something (like 20-30 miles a day for weeks) does not mean it’s a good idea.

[Roger Caffin]

One would like to know just what he was eating. Must have been pretty weird. All calories and no other nutrients?

Cheers

[Bonzo]

All calories and no other nutrients?

I see more of that kind of food than anything else.  Tons of sugars and fats, but nothing much in the way of actual nutrition.  I think the theory is “doesn’t matter what I eat; I’m just going to burn it off”…and while that’s true, it leaves a lot of important stuff by the wayside.

[HkNewman]

In otherwise healthy mostly young adults, I’d bet a junk food diet is responsible .. looking at only calories.   It would be interesting to see if there were any differences between those eating premium dehydrated meals with some vegetables thrown in vs (remembering the old song) the “junk food junkies”.

… see ‘70s song

The military, who also have young mostly men, under a lot of physical stress tries to deliver at least a hot dinner with balanced nutrition.

[DWR D]

“…the theory is “doesn’t matter what I eat; I’m just going to burn it off”…and while that’s true…”

Not necessarily true. I used that justification for years while eating junk and exercising hard.  Ended up with some real health issues. If I could go back and do it differently, I would. Still, every genetic makeup is different… some can get away with things other can’t… but the problem is, mostly we don’t know which genes exempt which people from what things… yet. But it does serve as a great justification to do what you want.

 

[Mark L]

> One would like to know just what he was eating. Must have been pretty weird.

Section 4.3.2:

“Before the hike, the hiker was mainly consuming rice, fresh vegetables, chicken, and beef. During the hike, the hiker consumed more calorically dense food items such as candy, pastries, nuts, jerky, dried fruit, ramen noodles, instant mashed potatoes, protein bars, and peanut butter. ”

Most of those seem like staples to me. But there’s no need to debate the accuracy of “poor diet” here. After all, the principal author, Thomas Heinbockel, a research scholar in human physiology, is also the subject being studied:

https://www.colorado.edu/asmagazine/2021/03/30/junk-food-and-big-miles-may-not-add-how-thru-hikers-hope

I’m not sure how many thru hikers are on BPL. I imagine this topic is only an issue for a 3-6 month outing with limited supply choices due to availability, freshness, and weight restrictions. Most of us are out a week and then back home with our salads. And most thru hikers aren’t averaging 24 miles a day, and doing the PCT in 112 days.

My takeaways:

-Exercise doesn’t make up for poor diet. This is in contract to a great majority of thru hiker YouTubers who talk about pounding Snickers without worry “because you burn it off.” No.

-There are contrasting studies, but it seems that just as with cycling, sweating does a lot more than just alert us to the need to drink more water. Mineral loss over time becomes a real issue and must be addressed.

-For me, it’s actionable data. I’d likely be more apt to toss some sardine tins and dehydrated yogurt into my food bag to get some bioavailable calcium and extra D. Committing to a bear can opens up options I would normally not consider.

-A young, extremely fit male is going to have a much broader margin of error than an older hiker. Therefore I am not dismissive of it. I suspect it takes more for him to get to that point than it would for me, and undoubtedly his young body & fitness level would allow a more rapid recovery. So it’s a worthy study and I don’t toss it aside but will use it to learn and act.

I think it’s valuable information for thru hikers. Nearly all thru hikers I’ve met or read the journals of the last 25 years admit to eating exactly like that fellow, or worse, and none of them were in as good of shape as he, at the prime of his life, too.

Or maybe the experience is so worth it that many simply don’t worry about it <shrug>. I have to admit, I reach a point in my own health where I feel like I need to de-stress about it all and just go grab a six pack and live life. So there is that aspect also: the psychological benefit.

 

[DWR D]

“In otherwise healthy mostly young adults, I’d bet a junk food diet is responsible .. looking at only calories.”

Not…. studies have shown that junk food negatively affects even children and sets them up for coronary disease and other major illnesses. That’s why there has been a trend toward elementary and high schools eliminating junk food from vending machines and cafeterias…

 

[DWR D]

Its only takes a tiny bit of common sense to know that when your are stressing your body more, good nutrition is even MORE important; not less.

 

[HkNewman]

.freshness… Most of us are out a week and then back home with our salads

Many parts of the PCT have access to restaurants, but young people especially may be drawn to pizza exclusively.  It’s a mostly young crowd in vacation mode.

Some parts of the PCT are remote (Sierra, Cascades past “Kraker Barrel” @ Whites Pass [which serves home grown veggies fwiw], but most segments have town stops which also cater to other tourists.  Probably moreso on the AT.

Think it’s mostly voluntary (though leftover pizza does make a good breakfast).

[Gerry B.]

It reminds me of an interview I saw or read years ago with the founder of ULA Equipment, Brian Frankle.  When he did break away from work, he took some pretty serious extended hiking trips and he emphasized that he always ate healthy wholesome meals while on the trail, including a lot of fresh food.  And I remember him saying that he never lost weight on a long hike.  Unfortunately I do not remember details of his typical menu.

[John S.]

I knew I had seen this discussion somewhere. It was this article.

https://www.outsideonline.com/outdoor-adventure/hiking-and-backpacking/could-thru-hiking-be-bad-for-your-health/

I think the original paper is junk, due to the limitations and his drawn conclusions based on incomplete data (wouldn’t even give a detailed diet for his own “study”). Reddit had an interesting thread on this.

Maintaining muscle mass during a thru-hike from bodyweightfitness

Overexercising (and losing too much weight in the process) is never great on the body. Do everything in moderation. The reddit Brenda Braaten paste is good.

[Mark L]

Thank you John. Brenda’s page is indeed good, and she discusses bone maintenance, calcium and so on:

http://www.thru-hiker.com/articles/pack_light_eat_right.php

My breakfast staple has always been instant oatmeal with raisins, nuts, seeds, etc. tossed in. To rinse out my pot I then add in instant milk with a packet of Carnation Instant Breakfast. Those two alone bring you up to a respectable 600mg of calcium to start the day, not even counting the nuts.

Brenda doesn’t cite her sources, but she states under the “minerals” section:

“By carrying an unaccustomed load on your back, the skeletal system will be receiving messages to increase bone density in your spine and lower extremities. The pull of the muscles on your skeleton will also send signals to lay down thicker bones. (Women: backpacking is a wonderful way to decrease your risk of developing osteoporosis because it strengthens your skeleton.”

I’ve searched quite a bit for studies on this but haven’t yet hit paydirt with anything of quality. I have emailed her to see if she can provide a source.

Mark

[Murali C]

Tour de France cyclists who lose bone mass have the best chef’s – private chefs who cook food for them. These guys avoid steaks etc – highly disciplined athletes (with respect to food, recovery etc) who still lose bone density. So, while the paper cited here suggests food – I am not so sure that it tells the whole story. It will be interesting to see what kind of bone density our football players and basketball players have or have lost over time.

The PCT hikers do this for 4 to 5 months while professional athletes do this year in and year out for many many years and throughout the year.

The study just looked at one person as it is difficult to study a bigger sample size etc. While it is interesting, I don’t think we can draw broad conclusions from one person.

[Roger Caffin]

These guys avoid steaks etc
The mind boggles! Meat is a really good almost complete food in many ways. Digestion may take a little longer than really light foods, but all those wonderful nutrients. . .

We did a double stage in the French Alps one year (2+ month walk with packs), and staggered into a restaurant in the valley late in the evening. OK, steak and veg. When Sue’s steak arrived it was huge, and I thought to myself that she would only be able to eat about half of it. I might get to eat some of it, although mine was also huge. Later on, when I had taken the edge off my hunger, I looked to see how she was going with this mammoth steak. How much was left? Errr – it was almost all gone, Sue showed no sign of stopping! We needed that!

Did this sit on our stomachs in the morning? Not a bit. We sailed up the next high pass like a beaut.

Cheers

[W I S N E R !]

So I was listening to a podcast in which an MD was strongly cautioning other health practitioners to approach an injury diagnosis and how they present it to a patient with extreme caution…

…because they found that psychologically speaking, that diagnosis would often lead to a negative spiraling mental state that could in fact cause a person to quit the very physical behaviors keeping them alive.

So if the person in this PCT study never had any of their body composition or arterial function measured, what would have happened? Would it even be a meaningful, appreciable change? My wager is that they would’ve kept truckin’ in blissful ignorance, but with a diagnosis run the risk of pulling back from something they love.

Case in point: I had some shoulder pain…injection MRI said it was a torn labrum and two rotator tears. Prior to my diagnosis, I was doing Jiu Jitsu…just with a little shoulder pain. Post-diagnosis: I’ve quit Jiu Jitsu at the strong urging of my ortho, I’ve gained ten pounds, and I’ve largely lost a community that I loved. Frankly, I was better off not knowing, and shoulder be damned, I think I need to go back.

So what if not doing the PCT is the worst thing you could do to your health, by way of making you more sedentary than you would’ve been? By way of losing your spark and drive out of some fear over a physical issue that may not even impact your quality of life? And even so, what if we need to give a little to get a little…what if some of us would wither without the adventure, even if that adventure causes some physical trouble?

 

[Murali C]

I am not sure about the exact science behind this. Many of these guys avoid red meat while competing I think. They monitor their weight and power levels incessantly. There is a magic number that tells them they can fly up the mountains. These guys have 3 to 4% fat levels and are very careful ingesting more fat.

Novak Djokovic is vegan. Tom Brady – American football star here in US eats mostly plant based food. Basketball star Lebron James avoids red meat is what they say. These guys spend a million dollars on nutrition every year in the hope that they can keep playing in their late 30’s, 40’s etc at a very high level – while earning 20 to 30 million dollars.

[Roger Caffin]

Yes, but WHY?

A somewhat cynical and biased opinion follows:
A lot of these people have little or no knowledge of medicine or nutrition, but they are ‘very keen’ to prolong their status. So they are very susceptible to the latest food fads – along with millions of others.

Sue and I have a ‘normal’ or classical diet from 50 years ago, with very little fast food (or none) or fads. We go jogging every second day. I spend time every day working on the farm, and so does Sue. We have had COVID a couple of times, not to mention Long COVID, but we keep going. I am 77. We eat meat several times per week.

So where does that leave us?

Cheers

[AK Granola]

Too many variables and a limited “study” if you can call it that. But, sugar. Every through hiker I’ve ever met and plenty of shorter mile backpackers too, (including me, sadly…) eat a lot of processed sugar. Not in moderation. It’s in all day meals and snacks. If I were going to try to pick apart a cause of bone mass loss, I’d start with sugar consumption. Until something conclusive comes my way, I’m having a glass of wine. Cheers! you only live once, hike on.

[YoPrawn]

Vitamin K2 is important for proper calcium allocation to bones, which is something we need from leafy greens. Let alone the lack of calcium, and in usable forms at that.

Might turn out that eating Mountain House for half a year, while doing an Olympic physical feat, MIGHT be bad, eh?

Yeah, I know, total conjecture.. ;)

[Murali C]

Roger – you are living the Blue Zone life – you will live to be 100!

Here in the US, I know whatever I eat is ultraprocessed – accept that and carry on! Most of western countries make food to prolong shelf life, maximize profit and cater to the busy lives folks live out here. I mean, if I eat pasta in a restaurant – is the pasta freshly made in the restaurant or is it store bought? My grocery store pasta is ultra processed that will last a long time. Vegetables/fruits easily last 2 to 3 weeks here. My so called multi-grain bread that is supposed to last a few days lasts 2 weeks easily! My organic milk lasts a month or more. I could do organic for vegetables/fruits – but, not very convenient as there are fewer stores that are farther away and are typically more expensive.

One of the fastfood restaurants that claims it is fresh – Subway recently came under attack for fish that doesn’t have much fish in it and chicken that has very little chicken in it.

Very difficult to control the food source unless I have my own farm and grow chickens and vegetables etc. Anyway that is life! I think our bodies are amazing and will adapt to this lifestyle. Do I want to live to 100? No. I tell my friends and family, 75 is good for me as all problems start after 80! As long as I am healthy till 75, I am good!

There is an obseity pandemic here in the US and I suspect all over the world – but mostly because people are just too busy with work and don’t have time to exercise and smartphones are not helping as it enables a inactive lifestyle.

I am originally from India and remember getting fresh milk from cows/buffalos every day – and this was in a big metropolitan city back when I was in middle school – late 1970’s, 1980s etc. Getting chicken was going to a street market where the guy asks you for the weight of chicken you want and then he slits the throat of a chicken he picks, throws it in the cage till it dies, then removes feathers and prepares the chicken for you:-)

Backpacking aggravates all of these food issues…meaning the food is even worse! But as Wisner said – whatever – I will eat the processed food as I love backpacking and going out for a month every year. Our bodies are amazing and they will adapt!

[Roger Caffin]

Roger – you are living the Blue Zone life – you will live to be 100!
Or until the next pandemic for which all governments will (again) be totally unprepared.
It WILL come.

Cheers

[Bonzo]

Very difficult to control the food source unless I have my own farm and grow chickens and vegetables etc.

I have to disagree, there: it’s not difficult, it just takes a bit more time and (sometimes) more money.  My partner and I have to watch our diet closely because of the ultra-processed and preserved nature of the majority of the options at the grocery store…but the simple way around that is to just use whole ingredients and prepare your own food.  It’s not controlling the source, but rather picking the better options.  I bake twice a week and we always have healthy bread available; the same goes for cooking meats and vegetables.  I buy local things when I can, straight from the producers, and we try to waste as little food as possible; lots of leftovers get repurposed in our home.  The result is a grocery bill that’s only about 5% greater, on average, and a few hours of good time spent in the kitchen.  The life adjustment that allowed those extra hours and extra pennies was more difficult than finding healthy ingredients.

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