Hi Dean

True, very true. There ARE significant style differences between Australia and America. Australians are, as you suggest, a whole lot more blunt. I get reminded of this at regular intervals, and then forget again. :-)

Cheers

> Surely someone who spends so much time in the vicious Australian scrub would know...
I make my own trousers as well, and stuff does NOT fall out of the pockets on them.

cheers

Hi mark

> Even in the Arctic, active humans should hydrate more often than that (2 hrs)

Citation to published scientific work to support that?

Bear in mind that we do have the counter-evidence that many walkers do only drink every few hours - and go just great.

Cheers

Oh no, now we need 2 hour hydration timers!!!!

Comparative research articles are useful, I think that having subjective input included is a very valuable addition to the data.

Roger's viewpoint is shaped by how he uses a pack, what he stuffs in it and where he goes when wearing it.
Roger has his opinions as do the rest of us, use them as data points in how you choose a pack to suit your needs.

I much prefer opinionated reviews to some of the mainstream ones that mainly list out features and are written just too carefully to offend no one. Why? Because the opinionated ones will regularly get me "comparing and contrasting" with my own style -- and help determine whether the gear piece will work well for me.

Edited by ben2world on 09/18/2010 10:29:09 MDT.

Roger has his opinions as do the rest of us, use them as data points in how you choose a pack to suit your needs.

Exactly, we all should do our own thing and find our own way. In the instance of Part 1C I'll use his opinions/experience in the report to educate myself on the design features found amongst the various internal packs of the world that I don't have access to or don't care to try. Rogers opinions/experiences also further confirm my own preferences and feature choices in an UL pack, and that the method in which I hydrate is simple, sound, and has been successful for me.

I'm thankful my trips don't require me having to bushwhack on a regular basis, shoulder pocketless packs made out of heavier denier nylon, rely on heavy internal framed systems, and adhere to hydration practices that seem to defy common sense and my idea of what's logical. But I sure as hell enjoy reading accounts of individuals who do! When a majority of my mass in weight consists of water, water being the main transporter of numerous vitals, glucose, electrolytes, and oxygen, "every 2 hours or so at the most" just isn't going to cut it for me and I prefer an UL pack that facilitates efficient hydration for me. Dare I say I want my body to perform at it's best when I'm hiking on or off the trail.

"Why? Because the opinionated ones will regularly get me "comparing and contrasting" with my own style -- and help determine whether the gear piece will work well for me."

EXACTLY!!!! Thanks Ben.

Todd

In the USA, the most referenced article on fluid replacement (before, during, after) is the position stand from the American College of Sports Medicine.
http://tinyurl.com/23gvbq5 (pdf file, 196 KB)

There are numerous websites that reference that information, admittedly aimed more at runners, but still good information. In that article is the recommendation to replace fluids at the rate of sweating, for optimal performance (avoiding >2% body weight loss from water deficit).

"The goal of drinking during exercise is to prevent excessive dehydration (>2% BW loss from water deficit) and excessive changes in electrolyte balance to avert compromised exercise performance. The amount and rate of fluid replacement depends upon the individual sweating rate, exercise duration, and opportunities to drink. Individuals should periodically drink (as opportunities allow) during exercise, if it is expected they will become excessively dehydrated. Care should be taken in determining fluid replacement rates, particularly in prolonged exercise lasting greater than 3 h. The longer the exercise duration the greater the cumulative effects of slight mismatches between fluid needs and replacement, which can excessive dehydration or dilutional hyponatremia." (typo, word left out, in last sentence I think)

"It is difficult to recommend a specific fluid and electrolyte replacement schedule because of different exercise tasks (metabolic requirements, duration, clothing, equipment), weather conditions, and other factors (e.g., genetic predisposition, heat acclimatization and training status) influencing a person`s sweating rate and sweat electrolyte concentrations."

BOTTOM LINE: NEVER TELL ANYONE HOW THEY SHOULD HYDRATE THEMSELVES.

Edited by jshann on 09/18/2010 12:23:51 MDT.

I have only used a bladder system on one multi day hike and if anything I think I over hydrated, which can also be problematic. However, when I used to have my water bottle in my pack and only drunk at rest stops I think I probably under hydrated. I have settled on having water bottle holders on my shoulder straps and this works for me. I am also experimenting with Perpetuem, which supposedly doesn't work well in a bladder system.

I know what to expect from Roger and enjoy his reviewing style. It isn't the way I would do it, but variety is the spice of life etc.

Roger

I am not suggesting that you do not share your opinion. What I want you to realize that the manner in which you chose to phrase your opinion matters. Especially for someone in your position of influence.

I am suggesting and imploring you to write your opinion into your articles in a more off handed manner that doesn't just happen to question or insult some of your readerships' intelligence or their choices'. I think more then just a minority would agree with that. I would never have vocalized if you had the tact to acknowledge, in your writing, the fact that some folk actually might use a system that's different from yours. You're a smart guy Roger, I thought you might understand that you trap more flies with sugar then vinegar.

You finally owned up, I a way I suppose. I guess I found the "negativity" that you bemoaned early and often as a direct result of your choice of language. I felt it was a rather obvious and that you really had no room to bemoan commenter's "negativity" as you yourself touched it off at start with your original language. That's what I am getting at with the idea of a writer's responsibility, your words have more effect then you give them credit for.

Obviously I don't know you as well as you suppose I do. Strangely, you suggest that I should by your most recent response. I quite honestly don't know what to tell you. In general, I try and take people here and elsewhere at their word, or by what they say or write. I don't normally live or work with you so appealing to your personality doesn't help either of us much at all.

Now if I already known such things about you, perhaps I might have just gone on my jolly way with no harm and no foul. But that's not how the Internet works. I'm here and you're there, and I can't discern who you are as a person through a couple articles and a few forum posts. So please don't expect me to know how thick you skin might or might not be.

I am asking that you realize that you will be repeatedly commented on in a similar vein by other joe-ultralights who don't know you or your personality. They take you at your word for what you decided to write. I am only offering this as advise that might improve your readership and stop this pointless re-testing of your skin's thickness in what seems to be a perpetual theme here.

Soldiers aren't the only ones who can be too rough around the edges in both word and action.

Peace.

Edited by csforstall on 09/18/2010 15:38:31 MDT.

From intro [1] ”Similarly, it has been documented that minor dehydration (i.e., -1 to -2% of body weight) augments core temperature and cardiovascular strain that the increase in these variables is directly related to the thismagnitude of dehydration accrued during prolonged exercise and that the optimal rate of rehydration approximates the rate of sweat production [2].”

From [3]: “Healthy older subjects may be more prone to dehydration than their younger counterparts because of a blunted thirst sensation leading to a reduced fluid intake ([4], [5])”

[1] further states that one should keep drinking on par with sweating rate and in excess of sweating rate in hypo hydrated state.

Refs
[1] ARMSTRONG, MARESH et al (1997), “Thermal and circulatory responses during exercise: effects of hypohydration, dehydration, and water intake”, J Appl Physiol 82:2028-2035, 1997.

[2] Montain, S. J., and E. F. Coyle (1992). “The influence of graded dehydration on hyperthermia and cardiovascular drift during exercise”. J. Appl. Physiol. 73: 1340–1350.

[3] P. N. Ainslie et al (2002) ,” Energy balance, metabolism, hydration, and performance during strenuous hill walking: the effect of age“ J Appl Physiol 93:714-723, doi:10.1152/japplphysiol.01249.2001

[4] Kenney LW and Chiu P. “Influence of age on thirst and fluid intake.” Med Sci Sports Exerc 33: 1524–1532, 2001

[5] Sawka MN and Montain (2000) “SJ. Fluid and electrolyte supplementation for exercise heat stress. Am J Clin Nutr 72: 564–572,”

Edited: 0h10 (GMT+1)
Edited: 10h48 typo on percentages updated

Edited by P9QX on 09/19/2010 02:49:38 MDT.

@Travis

You've got me completely confused.

quite an absolutist statement. While I agree that the chances of the bladder popping are very small, statements like this could benefit from the same criticism directed at the review.

Absolutist? I am hardly commenting from the left field of philosophy. My comments are directly from experience, and I was providing countervailing evidence. Now, as I have said in other points in this discussion I felt Roger's comments on hydration bladders are not backed up by any research or evidence. I am offering my own evidence to support my side, I am not sure why you think this is so wrong and "stand-offish" on our part.

This lack of research is rather unusual on Roger's part as he is one who always seems to research everything, but when it comes to hydration bladders he appears to have not done his homework. I'm not asking for much when I ask Roger to produce data that backs up his statement. You Travis are the one who is demanding absolution of the original writer.

Again, I'm not against constructive criticism, but many people in this thread took on a viewpoint that is quite stand-offish

I must ask you Travis, since when has it been "stand-offish" to ask for evidence?

I think you are off your rocker if you don't take every statement with grain of salt. And its not asking much for Roger to proffer evidence to back his up his claims. How is that not constructive? Why should I absolve the writer if his claims on a small part of his article are indeed incorrect?

>> Surely someone who spends so much time in the vicious Australian scrub would know...

>I make my own trousers as well, and stuff does NOT fall out of the pockets on them.

This is exactly the kind of thing you do that irks people, man. Just write in your review "I use homemade pants with well designed secure pockets, thus I don't find much use for zip pouches on a pack's waistbelt. Those zip pouches may be more valuable if your pants pockets aren't too secure". Geez.

Edited by El_Canyon on 09/18/2010 17:22:02 MDT.

Charles,

"Absolutist": noun- any theory holding that values, principles, etc., are absolute and not relative, dependent, or changeable.

Even though Roger was giving his personal thoughts on water bladders, albeit provokingly worded, you counter with a statement that is full of absolutes. Your posts are also filled with the same type of rhetoric you complain about in the review.

As far as being stand-offish...Asking for evidence is not. The way people went about it is.

"I think you are off your rocker if you don't take every statement with grain of salt."
---back at ya. Works both ways. You and anyone may certainly ask anyone else to back up claims, but your tone in some statements was again, no different than what many were complaining about in the review.

Hi John

> he most referenced article on fluid replacement
Thank you for that. A valuable scientific contribution. I do agree with your conclusion, that each person is different.

> prevent excessive dehydration (>2% BW loss from water deficit)
By way of reference, for everyone else to consider: I weigh ~64 kg. 2% of that is 1.28 kg or 1.28 L of water. There is absolutely NO WAY that I can drink that much water in the space of 2.5 hours of walking. Can you? Should you? (The answer to the last is No: you can kill yourself that way.)

* Typically we have breakfast and a good drink. Then we walk for 2.5 hours and stop for morning tea/coffee Total fluid intake at morning tea would be about 0.4 L each.
* Then we walk for 2.5 hrs to lunch, and drink maybe another 0.4 L each.
* Then we walk to snack time and drink maybe another 0.4 L each.
* Finally we walk to camp time. Over dinner and the evening we might take in about 0.8 L each - but that includes all the water I put in dinner etc.

How do I know this? Because I use 1.25 L PET bottles for water storage and carriage, and over the years I have carefully monitored our water consumption so we can camp on top of mountains without having to carry excessive amounts of water. I am not saying this to prove that PET bottles are the best; rather I am trying to explain why I can say we don't need to be sucking on a teat as we walk.
(OK, that last bit is inflammatory! So take it as it is intended, with a grin. Remember: I am a highly biased Australian.)

Cheers

" I am a highly biased Australian.)"

Reminds me of that other highly biased Australian -- Mel Gibson. :)

This is getting pretty old fast. When you come right down to it Roger is probably one of the top 5 reviewers at BPL and his Engineering background sets him apart as well as his ability to build gear. His pack and tent are at odds with most other thinking but I admire that . From my own perspective I'm still not convinced that external frame packs aren't superior in concept and sometime execution and I've been backpacking since 1972. His take on cooking in tents and Co2 has been eye opening. I'm still waiting for the ultimate article on pot circumference to complete the others. Let me put it this way-I've been tuned up by him on occasion but so what I can take it , but frankly I think BPL is lucky to have him. Consider that Ray Jardine came from a similar background and turned Backpacking upside down and then got trashed at BPL for being a mystic and weirdo. Well, artists who are engineers are the antennae of the race pardon me Ezra Pound, and you might not be so light or different or quilted or tarped without takes like this.

Hi Cas

> ”Similarly, it has been documented that minor dehydration (i.e., 21 to 22% of
> body weight) augments core temperature and cardiovascular strain

Access to ref 2 requires a subscription, which I don't have.

But I really do hope you have a typo in your quote! dehydration by 21% of body weight means I would have lost over 12 kg of water! I'd be dead, most likely.

Cheers

> Reminds me of that other highly biased Australian -- Mel Gibson. :)

Don't know him. What does he do?

Cheers

Hi John

> I'm still not convinced that external frame packs aren't superior in concept
Ahem. The packs I make do have an external frame ... :-)

> I'm still waiting for the ultimate article on pot circumference
It's coming!
Yes, a lot of the metrology has been done (you can thank Tony Beasley for that), and the results are quite interesting. Some anticipated, some not. Stay tuned. No pre-releases though.

Cheers