I’m curious what role boat weight plays in terms of the likelihood of paddling-related injury.
I own several kayaks and my typical workout is around 2 hours of aerobic paddling. Two of my boats have a weight difference of 15 lbs. (31 vs. 46 lbs.) Altho paddling the heavier boat requires noticeably more effort, it is less clear to me what, if any, the relationship is between moderate boat weight differences and injury (other than that lighter is intuitively better.) I am not talking about great weight differences such as loaded vs. unloaded boats, just empty boat weight.
Any thoughts?
Boat weight and injuries.
I’m inclined to think heavier boats are more likely to cause new injuries or agravate previous ones when loading or unloading them and getting them in and out of the water. I think my agravation of my periodic sciatica last year would have less likely if I hadn’t been trying to drag my relatively heavy Pungo(listed as 49lbs.), all of my gear including an 8lb.anchor, and myself up a steep muddy bank from the Shenandoah.
Non Traumatic Injuries
due to overtraining and stress to the musculoskeletal system are due to the individual’s attempt to do too much and too soon. Also related is not having a “balance” exercise regiment that develops complementary muscles that help support the primary muscles in a particular activity.
In other words, I don’t think the slight weight difference in boats will matter much. More important that the paddler learns to pay attention to his and her body, have a reasonably progressive regiment for improvement in paddling, and does exercises that develop complimentary muscles, as well as understand the use of training cycles which allow for down time to allow the body and mind to recuperate.
sing
warm up
I bet most of the injuries occur when trying to get the boat off the car and into the water. Your muscles aren’t warmed up or ready for the sudden lift.
Once you’re on the water, if you don’t go hard right away, you take some easy strokes at first to loosen up.
Weight is a very big deal!
I would have never had several of the injuries that befell me if I had started with 45 lb boats I have now instead of the 60 lb range of longer boats I used. Anytime you either bend over to lift or start lifting past neck level, the forces on your body become almost exponential. I mean a 38 lb kayak lifts up to neck level and as you hump it up to the roof rack if feels like it gains another 30 lbs! Somewhere OSHA has a chart showing workers what a 10 foot ladder exerts in force as it’s lifted overhead.
Keep in mind you never hear anyone crabbing cause their kayak/canoe is too light and they want something heavier. Buy as light as you can afford and go smaller in length to get the boat lighter if you are a rec paddler. Many people sadly gave up on canoeing since most of the early rec boats were 70-100 lbs. I think that will prove true with many of the 60 lb kayaks people are car-topping. They won’t stay with the sport or paddle as often.
no correlation
you have a choice. If there’s a pile of sand to move you can chose to load the wheel barrow with a lot of sand so it’s hard to move or you can load it to where you are comfortable moving it.
If you have a big blade with lots of grab you can torque on it with every stroke or you can use it according to your limits. If you’re paddling a kayak that’s 15lbs heavier,so that the kayak/paddler combo is 225lbs instead of 240lbs for example, then you’ll accellerate slower. If you’re launching through surf either your forward stroke is adequate to getting out in time,or it’s not.
Aside from lifting, there’s no relation
I have a 33-lb SOT and 61-lb sea kayak. Though the former is easy to carry/lift and the latter is a bear, the heavier boat is EASIER to paddle due to more efficient hull design. I paddled 2 laps (about 15 miles) around a local reservoir at between 3.25 and 3.5 mph ave. and was noticeably more tired than when I do the same–at 1 mph faster speed–in my 61-pounder.
Now, if it were possible to obtain the exact same kayak in 60-lb layup and 30-lb layup, there would probably be less strain on your body in paddling the latter. But since the boat is floating in water, which makes the weight difference less noticeable than on land, I doubt it’d be much difference except for long-distance outings. Have you ever lifted another human being on land and then lifted them in the water? Yeah, big difference.
If you want to save your back and are not already doing so, use a kayak cart to haul your heavy boat from car to shore. $100 for a nice one is much cheaper than buying a composite kayak of the same type to save 5 to 10 lbs of boat weight.
F = ma
is the formula relating force, mass and acceleration. It describes the force required to accelerate a given mass.
It is clear from the formula that the force required to accelerate a greater mass by a given amount will be greater than that required to accelerate a smaller mass by the same amount. In the case of a kayak, note that the force required to produce this acceleration is not determined by the weight of the boat in water (Archimedes principle) but by the mass of the boat which is fixed.
Thus, if the rate of acceleration of a kayak of known mass is known, then the force required to produce that acceleration is easily calculated. And since a kayak is accelerated slightly each time a stroke is taken, the formula will apply to paddling a kayak even at a perceived steady state.
But because F = ma denotes a linear relationship, it would seem to me that for identical boats differing only in mass, a given percentage change in mass would produce the same percentage change in force required for a given acceleration. If true, this would seem to allow one to determine the relative (not actual) differences in force required to paddle kayaks of different mass merely by knowing the percentage weight difference.
Any kayak gurus out there who can comment more authoritatively?
I agree with JEM. I have injured
– Last Updated: Feb-15-05 4:30 PM EST –
myself on the water, but rarely and of short duration. Handling boats out of the water has caused me (and the boats) much more pain.To me , loading and unloading are the danger points.