Correct clothing and adequate hydration can prevent much, if not all of the serious discomfort. Limiting physical exertion and sensible food intake are also important.
Sunburn is preventable by eliminating exposed skin. I find this much more tolerable than smearing myself with greasy salves, and I’m not convinced that reducing sunburn chemically actually decreases the possibility of skin cancer. I do know for a fact that my body temperature and my level of comfort is much better when keeping the sun’s radiation off of me the old fashion way. With the advent of modern high SPF clothing this has become much more comfortable. Employing a lightweight full brimmed hat, a Buff to cover the face, sun gloves for the hands, along with long sleeved shirts and long pants, and lightweight breathable shoes, one can cover themselves almost completely. Even the undergarments can now be obtained made from thin synthetic materials that maximize breathability and moisture wicking. The use of sunglasses to protect the eyes goes without saying.
Information about food or nutritional intake is highly oriented towards adequate hydration but it is not limited simply to fluids; high quality nutritionally dense but easily digestible foods of low volume can also minimize discomfort.
It is very important to realize that hydration starts well before exertion and/or exposure to the heat. Ideally, the need to empty the bladder should exist before weighing the canoe as this indicates the body is flush from the start. That is a target I strive to achieve. Throughout the day, the need to urinate at least a few times should continue, which will eliminate the concentrated wastes that accumulate as the increased sweating removes water through the skin. If this goal is achieved the delayed fatigue seems to be minimized; I guess because some internal organs are being stressed less. Forcing liquid intake above normal desire during the drive, and throughout the day, is the only way to achieve this goal for me. The use of a reminder timer is the best way I have found to do it.
If a few liter bottles of water are brought along for the ride, and the timer is set to alarm every 15 minutes I can consume a few bottles during the drive without feeling like I am force-feeding myself. After weighing the canoe I switch to hydrating from my thermos containing flavored water, which then seems so much more palatable. Small differences can seem like big improvements. I spike that water with Key Lime juice and “lite” salt.
My usual food consumption schedule seems adequate and beneficial. It would seem that limiting the volume of non-liquid nutrition will minimize the blood flow to the stomach for digestion thus allowing maximal flow to the skin where evaporative cooling takes place. Foods that are easily digestible, like those employed by long distance runners, supply the needed energy but stress the digestion system the least. This is not the time for big lunches.
One curious food item that seems odd but through my experience seems to be very effective is a pickle. I actually prefer pickled okra, but I assume that is a very localized item. Why would someone want to eat pickles when fishing? Muscle cramps. Cramps are quite common, especially in the hands and fore arms when casting to, and fighting, a lot of fish when you are sweating profusely. I came upon this odd remedy from a friend who made it into the NFL. He told me during spring and their strenuous mid day sessions, the players were not allowed back into the training facility at the end of the practice unless they ate a dill pickle or drank a small cup of juice. The reason: to deter muscle cramps. I can attest that, at least for me, it works like magic. If the cramps set in – and trust me, hand cramps when the fish are biting are a real form of torture – eating a few pickled okra is a nice diversion while resting, but soon after I can feel the tightened muscles relaxing, usually within minutes.
There are a few physical items that can each add incrementally to comfort while out on the water. By far the most useful and often overlooked piece of extra equipment is a golf umbrella. Shade is heaven when out during the summer, unfortunately the mosquitoes and deerflies can make the real thing seem more like hell. Portable shade, aka an umbrella, can be utilized anywhere, and it is especially nice well out in the middle of the water where the bugs are minimal. Rigging a stable umbrella mount to cover oneself while paddling is an absolute paradigm shift.
Two other small items that add to comfort are as simple as bringing a soft, absorbent wash cloth to wipe the face. A container of fresh water to rinse the cloth significantly increases the realization that this minor item can feel more like a luxury. A similar but high tech item called an artic cloth by one manufacturer, made of new high tech synthetic material, can also be wet with that extra source of clean water. The material is draped over the shoulders in contact with the neck. As the water evaporates the cloth cools. By alternating the exposed side of the cloth for the side in contact with the neck one can continually expose the skin to a much cooler than ambient temperature. The theory is the blood flowing to and from the brain is then additionally cooled. It might be only and incremental difference, but in this environment every little bit helps.
It probably goes without saying but it is best to take on a low energy cadence to everything, and especially paddling. It does not pay to rush while the heat is on, and doing so seems to quickly result in becoming aggravated, a sure sign that the heat is getting to you.
Putting it simply: heat stroke can take you out. It is one of the few real dangers. If things take this turn for the worse while canoeing, even a moderate distance into the wilderness, you are in serious trouble. Medical attention is essential but probably not able to reach you. Getting back, just to the vehicle, requires more exertion than you can afford. Again, simply put, you do not want to go there. This is a somber realization that one must take very seriously or you can quite actually kill yourself. Confusion and syncope (fainting) are mental conditions associated with heat stroke that only compound the problem: you cannot trust yourself to make a good decision or even remain conscious.
So… given how unbearably uncomfortable the endeavor is guaranteed to be, and given that it might actually be life threatening… why would someone even consider trying to fly fish in such conditions?
Take a guess.