Taking research with a grain of salt

Periodically you'll read the newspaper article about some study that has been conducted and be told that, as a result of the study, you should act in a certain way. The most common articles about research that I've read our about food and exercise. This article make some points about research on those topics to help us think more clearly about what researchers tell us.

Main points:

• The correlation between inputs (food, exercise) and results (disease, longevity, weight) tends to be much lower than the correlation between things like smoking and lung cancer.
• Much of the research has not yet been reproduced to see if the same results show up.
• Sometimes the way things are measured is not the most accurate. For example, participants may be asked to keep a diary of what they eat. It would be easy to say that people may not keep the most accurate diaries.

One team of researchers reviewed studies on the links of particular foods and cancer, and found studies linked just about everything we eat to cancer. Depending on the study, foods were either linked to cancer or had no link.

So the next time see an article in the newspaper breathlessly stating that something will help you live forever or will kill you, take it with a grain of salt (no doubt, salt is just fine, or is it?)

Nordic walking and load on the knees

One research article noted that Nordic walking may not reduce loads on walkers' knees, a possible selling point by some Nordic walking proponents.

• One reason offered is that walkers push off with the poles when stepping off with the foot rather than planting the poles when the feet land. Planting the poles when the feet land is said to distribute weight to the poles.
• Another reason offered is Nordic walkers take longer strides than when walking traditionally, and longer strides make for greater impact when the feet land.

People interested in Nordic walking shouldn't be overly concerned about this. Notice that the comparison is with normal walking, and walking is already considered a low-impact activity. If we compare it with running, then Nordic walking certainly has a much lower load on the knees.

Here are some thoughts about taking care of your knees when you're Nordic walking:

• Include warm-up activities that limber up your knees.
• Adjust your stride to account for load on your knees if it is a concern.
• For example, a shorter stride and less arm swing can reduce the impact when your foot hits the ground.
• When you do that, you'll find that you'll want to adjust the length of your poles. In my experience, shorter strides and arm swings mean shorter poles, and longer strides and arm swings mean longer poles.
• I like using my adjustable poles because during a longer walk, I have a tendency to vary my stride and arm swing.

Nordic walking versus walking with hand weights

Here's an interesting comparison of the effectiveness of Nordic walking and walking with hand weights.

Comparison	Nordic walking	Hand weights	What the Nordic Walking Guy says (based on experience)
Exertion	"…the real muscle exertion in the upper body comes from the backward/downward push"	"… the muscles lifting the weight forward get most of the exercise"	This has been my experience as well.
Range of motion	"…limitations in the range of motion because the sticks are fitted to one’s height and their benefit is derived from gripping the ground and pushing off, not being raised over head"	"Raising the arms and weights above the shoulder to overhead  (“Level III”) significantly enhances the workload during exercise."	The author of the linked article used fixed length Nordic walking poles. Adjustable models are also available (I use adjustable Nordic walking poles) and make it possible to give yourself different lengths during the same walk. For lower intensity parts of the walk, you can shorten the poles a bit. For higher intensity parts of the walk, you can lengthen the poles. Because modern poles have quick release gloves, you can let go and use the poles in an overhead pressing and other kinds of motion. As light as the poles might be, after some repetitions of the overhead pressing motion, I guarantee your shoulders will feel a burn. Try it where you are right now without anything in your hands. Just raise your arms overhead and start doing a pressing motion and see how quickly your shoulders start to burn.
Exercise variety	"…Nordic Walking definitely DOES NOT offer this variety of exercise. The same predominant exercise pathway is used throughout the effort without variation for the most part. Boredom may be avoided by the scenic nature of the walking path, but not by exercise variation for the most part!"	"numerous variations in exercise movement to not only work as much muscle as possible, but to avoid boredom!" "…can be used in some completely different way like swings across the chest to work “fresh” muscle groups while continuing to walk"	I am an avid Nordic walker and have found it easy to add variety to a walk by incorporating bodyweight exercises. For example, I can stop, do push-ups, and then resume my walk. Later, I can do squats. Farther along in the walk, I can do crunches for leg raises. This is possible because most Nordic walking poles have quick release gloves that make it convenient to quickly shift to a different form of exercise. If having heavier weights to your poles is the goal, that is possible as well. The conclusion of the matter is that adding variety to the walk is very possible.
Safety	"at times the Nordic Sticks seemed a bit more like “Trekking Poles” but they did their job of not only providing upper body exercise, but also making the hike safer.  In the event of a poisonous snake nearby, I’d rather have a Nordic stick handy if needed than a hand weight!"	We took the “rugged” trail first using Nordic Walking sticks. Later we took the “level” trail using HeavyHands. (We found out they were both equally rugged and probably would have done best with the Nordic sticks on both of them, but “oh well”! )	One way that Nordic walking poles made trail walking safer is because they have metal tips that can dig into the ground and baskets (like those on skis) that would keep the polls from seeking too far into softer ground. Personally, if I saw a poisonous snake on the trail, I wouldn't stick around to use the Nordic walking poles. I I would turn around and run!