Wednesday, 20 October 2010

On Trekking Poles

I have never used trekking poles. I have never seen the need. Whether that is a stoic retention of my current walking technique or the fact that years of football has meant that my legs are strong enough to canter a descent without assistance, I know not. Either way, I have not hitherto given them much consideration.

Two things have combined recently to alter that philosophy. Firstly, the use of a trekking pole (or poles) to set up an ultralight tarp shelter is something that I have seen done repeatedly. It is the very epitome of the UL philosophy - adapting shelter construction to put to use an item in a way it was not initially designed for. Clearly, I was never going to start using poles just to engage in tarp camping - to alter my walking technique for that reason alone would be ludicrous - but it sewed a seed of doubt in my mind. Secondly, during the TMB, one of my friends became injured and bought some poles largely to take the pressure of his ankle. They worked so well that I experimented with them for a while and was intrigued by them. As winter rolls in, trekking poles will become even more useful and are advised by almost every winter mountaineering leader I have spoken to. So what the pros and cons of trekking poles, in summer and winter, and in different environments?

To understand that, I needed to understand exactly what trekking poles sought to achieve. 



The Pros
In essence, trekking poles will spread the pressure of walking across more joints in the body - notably, they will reduce the pressure on the knee joints by permitting the arms to ease some of the bodyweight from the knees and through the arms onto the poles themselves - the
BMC suggests as much as 20% of the stress is moved to the arms from the knees. 

"When stepping down the physiology of the knee causes the articular cartilage of the knee joint to be squeezed dry of its lubricating and nourishing synovial fluid. This is why your knees will feel sore after a day of long descents. If the cartilage is repeatedly squeezed in this way, day upon day, it runs dry. The resulting friction will cause inflammation, pain and ultimately leads to a thinning and wearing away of the cartilage. Then bone rubs against bone and the result is osteo-arthritis." It cannot be stated any more clearly than that.

Poles also aid balance by lengthening the effective reach of the arms to permit the placement of poles onto terrain which grants the stability of 3 or 4 points of contact rather than 2. Through this increased stability, the pressure on muscles and joints in the legs is decreased as greater stability means less energy used maintaining balance.


Trekking poles also assist in ascending, even when in fact there is less pressure on the knees in comparison to descending, by reducing the weight on the knees by as much as 8kg per step. So, when considering the advantages descending, which seem obvious, the advantages when ascending are significant too. Additionally, the placement of the arms is equally important - having the arms moving in rhythm using a nordic walking style, raised above the waist as they are, improves blood circulation through the body, assisting breathing and therefore stamina. There are countless accounts of trekkers, trail runners and hillwalkers who have felt their stamina increased by the use of trekking poles. Poles also encourage improved posture, leading to a diminishing risk of back pain.

Studies published in
Medicine & Science in Sports & Exercise in December 2000 (CA Knight and GE Caldwell) and January 2001 (Wilson, Torry, Decker, Kernozek and Steadman) examined hikers wearing loaded backpacks and found that when the test subjects had trekking poles their walking mimicked that of an unloaded person - they had less joint stress and a lower heart rate. In addition, the poles created a better weight distribution for the subjects, which also contributed to the increased power they were able to achieve while using the trekking poles: to quote the abstracts - "By redistributing some of the backpack effort, pole use alleviated some stress from the lower extremities and allowed a partial reversal of typical load-bearing strategies" and "The use of walking poles enabled subjects to walk at a faster speed with reduced vertical ground reaction forces, vertical knee joint reaction forces, and reduction in the knee extensor angular impulse and support moment, depending on the poling condition used."

In a study by Northumbria University published
this year in Medicine & Science in Sports & Exercise, 37 men and women, regularly physically active, were split into two groups of equal fitness who then climbed Snowdon. One group was issued with and, most importantly, trained in the use of, trekking poles while the other group made the climb without. Food consumption, pack weight and rest were identical during both the ascent and descent. The participants' heart rates and exertion levels were recorded during the hike. Then, at the end of the hike, and at 24-, 48- and 72-hour intervals afterwards, muscle damage and function were assessed. 

Unsurprisingly, results demonstrated significantly less muscle soreness in the group using trekking poles. This group also demonstrated a reduced loss of strength and a faster recovery immediately after the trek compared to the control group. Self-rated soreness peaked at 24-hours in both groups but was significantly lower in the group using trekking-poles, both at this point and at the 48-hour point. In addition, levels of the enzyme
creatine kinase (which serves as an indicator of muscle damage) were much higher at the 24-hour point in the non-pole group, while the trekking-pole group's levels were close to the pre-trekking levels. 

The Cons
The cons are reasonably obvious. There is an initial financial outlay which can be significant - poles tend not to be cheap. Even Alpkit carbon poles are £60. They weigh around 250-500g per pair depending on the type and materials. Further, they increase total energy expenditure as arms are used as much as legs. The effect of this will vary from individual to individual but newcomers to poles will need to recognise this fact and get used to them and the potentially increased calorie requirements.

Additionally, poles need to be put away when not in use - there is a temptation to use them on technical sections when really, hands are the appropriate tool. They should be stowed and the lazy among us might be tempted to let them flap on the wrist loops.
Poles must not be used in situations where an ice-axe is required. The number of accidents, some fatal, in Scotland, where poles have been retained when an ice-axe should have been deployed has increased in recent years.

Using Poles
The correct rhythm for poles is the natural swing momentum of the arms. As in normal walking, when one leg moves forward the opposite arm does so. The same should be true of trekking poles. As legs shift weight, the aim then should be to push down on the pole, consequently reducing some of the weight usually transferred to the knees. Rhythm is crucial for the proper use of trekking poles and securing the full benefit.

On descents, poles should be cast further ahead so that they take weight. For long descents it is beneficial to adjust the height as mentioned above.


Similarly, on ascents the poles should be case slightly ahead, less so than on descent, and pushed on to help upwards movement. This pushing movement should be continued as the body moves past the poles. For extra upwards power on very steep areas, move the hand onto the top of the handle and thrust hard as the pole is behind the body. On very steep sections, both poles can be placed down ahead of the body and both arms worked at the same time to enhance the upwards power.

Poles that have lower grip extensions allow you to shift your hands down to these to quickly make poles effectively shorter.

Carbon Fibre vs Aluminium 
One of the advantages of carbon fibre is that it absorbs more shock than aluminum. It is also, obviously, significantly lighter. That said, although extremely strong, it is not as strong as aluminum. UL principles would dictate a carbon fibre pole but it would certainly need to be a tested, reliable pole before I considered carbon fibre as a material. Black Diamond, Leki and Mountain King all have great, durable carbon fibre poles in their range. Also, it seems to me, Anti-shock is an unnecessary feature that simply adds weight and a complexity that can only go wrong, or seize up in winter. Why would I want my poles to be dampened in any way, reducing the feel they give me through my hands and arms...?



Setting Pole Height and Wrists Straps
If it assists, here is the correct way to set the height of trekking poles:


  1. On level ground, stand holding the handle with the pole straight vertically.
  2. Adjust the pole's height so that your forearm is roughly horizontal (90° to your body).
  3. During long descents and ascents the ground slope changes, however still adjust so that your forearm is horizontal. On descents your pole will be longer and on ascents it will be shorter to help you on each type of terrain.

When using wrists straps, remember:
  1. Insert your hand up through the wrist strap from below, far enough that the wrist strap goes around the wrist.
  2. Move your hand down around the handle, twisting slightly, so that the wrist strap now goes under the palm.
  3. Adjust the size to give a comfortable but firm fit - it should vary tightness depending on the conditions and the likely need to stow the poles or to release them quickly. When putting weight onto the pole, the strap should be taking the strain.

Pole Locking Mechanisms 
The best way to deal with this simply, it seems to me, is to compare Leki and Black Diamond. Leki have a telescopic twist-lock system which is lightweight but prone to slipping in winter and I find it a pain to use in gloves. Whilst on the TMB I had a look at it and felt like throwing the poles off the mountainside. I'm sure you get used to it, but there you have it. The Black Diamond flip-lock system is heavier but
more reliable in winter and very easy to use. Consequently, it’s more likely a pole user will gain the most significant benefit of altering pole length regularly with this system, as compared with the Leki system, because it is so simple and quick. That said, Leki have just released a flip lock system called Speedlock. I have looked at this on You Tube and it looks so very complicated that I can hardly see the point. Also, it’s untested as yet and I would rather accept the weight penalty of the Black Diamond system. 


Remember to store the poles with the locking mechanism loosened to prevent freezing.


The next post from me is initial thoughts on the Black Diamond Alpine Carbon Cork poles...

13 comments:

  1. I've had a bit of a trekking pole journey, starting with a really cheap pair (to check I got on with them), then onto Black Diamond Expeditions, then Pacer Poles, then the extremely light Ti Goat AGPs.

    I decided to try the UL poles whilst experimenting with an umbrella, as their weight would permit me to carry them on my pack without too much weight penalty. I completed the 2010 TGO Challenge with them, but managed to break one in a boggy section that merely bent Andy's alloy poles. It was replaced free of charge, but whilst waiting for the replacement to arrive I returned to my Pacer Poles, and I have to admit my new Ti Goat pole remains unblemished. Pacer Poles are just so good.


    Designed by a UK physiotherapist specialising in biomechanics and an architect, they are endorsed by Chris Townsend who I believe uses them for ski-touring in the winter too, fitted with the optional snow baskets. There's an extract from The Backpacker's Handbook here:

    http://www.pacerpoles.com/reviews.html

    They look weird, but I wouldn't go back to 'normal' poles unless I was planning to carry them any great distance - they're not light. I just wish they had some form of external tensioning device like the BD Flicklocks - the supplied rubber glove just isn't the same!

    ReplyDelete
  2. I think what sold me on the BD Alpine Carbon Cork poles is the fliplock which is so simple and so reliable, especially in freezing conditions. Perhaps I'll get another set for summer or perhaps I'll just deal with the fact they are just under half a kilo. The LT4 poles seem good but I'm intrigued by the TG AGPs - 198g without baskets. Wish TiGoat would sort out their website pictures though - in this day and age of digital photography!

    ReplyDelete
  3. Carbon poles break more easy. I have never folded a aluminium pole but my Carbon Pacers folded. Lots folks (Philip Werner) have reported folding carbon poles. Black Diamond poles are my main ones at the moment until I get new Aluminium Pacer Poles. Pacer Poles are superb Maz. Used Trekking Poles for over 13y now. Wont backpack without them. The ultimate proof of how they work is how many old hillwalkers you meet who where going to have to give up hill walking with bad knees. They tried poles and kept on walking. Trekking poles work and you wont regret using them. Just remember they are strictly not needed and add to your overall shelter weight.

    ReplyDelete
  4. As you observed in my post on the BD poles, it was the locking system that swung it for me! I'm looking forward to using them - my thigh muscles are strong but my knees are suffering from too many bad challenges on sunday morning football pitches when I was young and foolish...

    ReplyDelete
  5. Maz, a well researched and written post. I use poles because they help with fatigue, my knees and importantly as I walk on my own a lot if I twisted my ankle,I would have some support.
    I have Leki poles, but I would like to try Pacer Poles.
    Mark

    ReplyDelete
  6. I went from no poles, to a staff, to GG LT4s. I never though I'd like two poles, but I got used to them surprisingly quickly. They are so light - although it's true that I do feel I have to be careful with them. I do find that the locking mechanism on the LT4s is a little slippery. Maybe I need to adjust them.

    Pace poles look interesting. I'd like to try them.

    It's amazing how your uphill speed increases with two poles though.

    ReplyDelete
  7. On another note, I find the "natural" walking rhythm (Nordic style) to be too rushed. I feel too frenzied walking like that, and it's not practical unless you are waling on a well-defined path. On more rugged ground, you simply can't walk Nordic-style. I generally use a more relaxed swing.

    ReplyDelete
  8. Pacer Poles do look interesting and I am a fan of well-researched ergonomics. Had they come with fliplock or similar I'd probably have gone for them.

    As for the Nordic Walking rhythm - part of gym routine is a cross trainer so the rhythm is one I am used to and find reasonable. I often watched it, thought, and I also thought it looked somewhat frenetic. I think I will settle into my own rhythm as I get used to the BD poles.

    ReplyDelete
  9. "When stepping down the physiology of the knee causes the articular cartilage of the knee joint to be squeezed dry of its lubricating and nourishing synovial fluid. This is why your knees will feel sore after a day of long descents. If the cartilage is repeatedly squeezed in this way, day upon day, it runs dry. The resulting friction will cause inflammation, pain and ultimately leads to a thinning and wearing away of the cartilage. Then bone rubs against bone and the result is osteo-arthritis."

    This does not fit with experience gained backpacking over the Munros with traditional gear. It is my knee ligaments which suffer. The ache disappears after a few days as soft tissues strengthen but then returns in the third month.

    For me, the worst con is cold hands. I now own some big gloves. Never needed before poles (and baldness).

    As far as the research on walking efficiency is concerned - interesting. That does fit with the feeling I have about what poles are doing for me. Also, I think, in rough terrain, they stop my centre of gravity from moving side to side, saving a lot of energy. On an early poling trip round Flowerdale, I feel they made the ninth hour far easier than an eighth hour would usually be so I estimate the energy savings as being around the 15% mark. Having said that, the longer a journey goes on, the stronger my legs get and the less need I feel for poles.

    ReplyDelete
  10. I'm interested because my knees have suffered at the hands of some unscrupulous footballers and also because the TMB taught me that they might well be useful in trickier descents - as always, it's a matter of personal choice but I am certainly looking forward to seeing whether they change the way I do things. I agree, though, that the longer I trek (ie the more days I am trekking) the stronger my muscles get but I am not convinced the same can be said for my joints.

    ReplyDelete
  11. I think, and could be wrong, that arthritis is an auto-immune disease. In other words, one we, me included, inherit a tendency for. I have read that autopsies showed that the cartilage of people who exercised tends to be thicker and smoother than the cartilage of corpses that didn't, but a genetic issue would undermine that, as would the twisting and turning of football. Again, I think I read that our knee joints are designed for forward progress. So, if you think your legs are able to get stronger while your joints don't, you are almost certainly right. Colin Griffiths would know.

    ReplyDelete
  12. "When stepping down the physiology of the knee causes the articular cartilage of the knee joint to be squeezed dry of its lubricating and nourishing synovial fluid. This is why your knees will feel sore after a day of long descents. If the cartilage is repeatedly squeezed in this way, day upon day, it runs dry. The resulting friction will cause inflammation, pain and ultimately leads to a thinning and wearing away of the cartilage. Then bone rubs against bone and the result is osteo-arthritis."

    This does not fit with experience gained backpacking over the Munros with traditional gear. It is my knee ligaments which suffer. The ache disappears after a few days as soft tissues strengthen but then returns in the third month.

    For me, the worst con is cold hands. I now own some big gloves. Never needed before poles (and baldness).

    As far as the research on walking efficiency is concerned - interesting. That does fit with the feeling I have about what poles are doing for me. Also, I think, in rough terrain, they stop my centre of gravity from moving side to side, saving a lot of energy. On an early poling trip round Flowerdale, I feel they made the ninth hour far easier than an eighth hour would usually be so I estimate the energy savings as being around the 15% mark. Having said that, the longer a journey goes on, the stronger my legs get and the less need I feel for poles.

    ReplyDelete
  13. I've had a bit of a trekking pole journey, starting with a really cheap pair (to check I got on with them), then onto Black Diamond Expeditions, then Pacer Poles, then the extremely light Ti Goat AGPs.

    I decided to try the UL poles whilst experimenting with an umbrella, as their weight would permit me to carry them on my pack without too much weight penalty. I completed the 2010 TGO Challenge with them, but managed to break one in a boggy section that merely bent Andy's alloy poles. It was replaced free of charge, but whilst waiting for the replacement to arrive I returned to my Pacer Poles, and I have to admit my new Ti Goat pole remains unblemished. Pacer Poles are just so good.


    Designed by a UK physiotherapist specialising in biomechanics and an architect, they are endorsed by Chris Townsend who I believe uses them for ski-touring in the winter too, fitted with the optional snow baskets. There's an extract from The Backpacker's Handbook here:

    http://www.pacerpoles.com/reviews.html

    They look weird, but I wouldn't go back to 'normal' poles unless I was planning to carry them any great distance - they're not light. I just wish they had some form of external tensioning device like the BD Flicklocks - the supplied rubber glove just isn't the same!

    ReplyDelete