The result is that each mile you run takes roughly the same amount of energy (about 110 calories for an average-size adult), regardless of your speed. But each mile on a bicycle uses vastly different levels of energy, depending on how fast you ride. From your own experience you know that maintaining 20 mph takes significantly more energy than going 18. Dr. Edward Coyle of The University of Texas, Austin determined average values of oxygen consumption by cyclists. He then applied these to develop the following table, which you can use to estimate the approximate caloric equivalence between running and cycling.

Cycling Speed Calories Conversion Table

M.P.H.   Cal. per mile     Factor
10          26              4.2
15          31              3.5
20          38              2.9
25          47              2.3
30          59              1.9

If you rode 20 miles at 20 mph, divide by the corresponding factor on the table (2.9). The result is 6.9 miles. So, in terms of energy expenditure, riding 20 miles at 20 mph is equivalent to running 6.9 miles. Both would burn about 760 calories (20 X 38).

These ratios have some important limitations. Coyle's derived conversion figures are for an average-size adult (approximately 155 pounds). A larger cyclist would divide by a slightly higher number; a smaller cyclist, by a slightly lower one. Wind, hills, specific fitness levels and other variables were not accounted for in the table, nor is drafting, which can reduce your energy expenditure by up to one-third.

The result of taking some NSAIDS may predispose kidney shut down during ultra-distance endurance events. For example, reseach had been performed to review Naproxen Sodium, the active ingredient in many anti-inflammatory over-the-counter medications, such as "Aleve." Results indicated that "The renal hemodynamic and tubular effects of such a celecoxib, a selective inhibitor of cyclooxygenase-2 (COX-2) to those of naproxen, a nonselective inhibitor of cyclooxygenases will occur in a sodium-depleted subjects. In one study subjects were not even exercising, the first day, both celecoxib and naproxen decreased urine output and sodium, lithium, and potassium excretion. Celecoxib had no effect on systemic blood pressure, but short-term transient decreases in renal blood flow and glomerular filtration rate were found with the highest dose of 400 mg on day 1. On day 7, similar effects on water and sodium excretion were observed. During repeated administration, a significant sodium retention occurred during the first 3 days. Researchers concluded that salt-depleted subjects, selective inhibition of COX-2 causes sodium and potassium retention, which may suggest that an increased selectivity for COX-2 does not spare the kidney, at least during salt depletion." (Clinical Pharmacol. Ther. 1999 Jul;66(1):76-84).

Of course, individual reaction depends on dose, degree of mineral losses in perspiration, and intensity. We do not recommend the continuous and consistent use of anti-inflammatory products during a ultra-distance endurance event.

"The Plantar Fascia is a muscle that attaches to the heel bone, or calcaneus. Plantar, in anatomical parlance, means bottom. Fascia is a term used to describe a tough, fibrous, gristlelike material produced by the body. Just beyond the point of attachment at the ball of the foot, the plantar fascia fans out, splitting into four separate slips which eventually become the toe webs.

The function of the plantar fascia is to hold the arch area up and prevent it from collapsing. (Remember that the fascia is made of a tough, fibrous material.) Unlike a tendon, which has the ability to stretch and re-form (like a rubber band), the plantar fascia does not have this stretching property. If the plantar fascia could stretch and re-form, your arch would collapse and re-form with every step. Obviously, this would not be very efficient unless you wanted to bounce down the road. The fact that the plantar fascia does not stretch is the very reason why it's responsible for causing heel pain.

If a foot imbalance exists, such as a flat or high-arched foot, the plantar fascia is repeatedly stressed at each step. (Remember that the fascia can't stretch - so something must give.) The weak point of this structure is its attachment to the heel bone; over time the fascia is actually pulled slightly away from the bone. This causes inflammation and the pain begins.

The body tries to reattach the fascia back to the bone. Unfortunately, every time one walks, more damage occurs further aggravating the problem. Think of it as a bruise on your arm that is constantly being irritated. The bruise won't heal and the pain will intensify; this is exactly what happens with a heel spur.

Classically, the pain is more intense in the morning when one first steps down. The reason is simple. For eight hours the body has had the opportunity to try to reattach the fascia and the repairing has commensed. Yet as soon as the person steps down, he or she pulls apart the healing area. This is extremely painful but clears up in several minutes as the area warms up.

The term "heel spur" is actually something of a misnomer. The problem is the pull of the plantar fascia off the heel bone, which leads to inflammation at the point of detachment. The term "plantar fasciitis" is more appropriate. A heel spur is a secondary finding seen on an X-ray. Over time (several months to years), the heel bone will begin to fill in the area that is being pulled with new bone. This is an effort by the body to have the bone reach out and reattach to the plantar fascia. This new bone formation is called a "heel spur." But remember, the spur is a secondary finding and not the cause of the problem. The problem is the pulling of the plantar fascia off the bone.

Pronation is the leading cause of plantar fasciitis, but even if you don't pronate to excess, you're not immune. Anything that puts abnormal strain on the plantar fascia -- overtaining, worn-out shoes, hard, inflexible shoes, too many hills - can lead to plantar fasciitis. Also, people who spend a lot of time walking around barefoot can incur plantar fasciitis."

Common observations on PF:

SURGERY IS AN ABSOLUTE LAST RESORT.

Cortisone injections are usually unnecessary (and painful).

Ultimately, the foot has to be mechanically redirected to correct for plantar fasciitis/heel spurs, so all wrapping techniques, cortisone injections, stretching, icing, etc., are only temporary. Mechanical redirection of the foot should often be translated into "buy the right shoe".

Make sure your doctor is experienced with and fully qualified to prescribe and fit orthotics and who understands the relationship of orthotics to alignment of the whole body, i.e., knee, hip, etc.

Early attention to the problem is essential. If you start to experience PF-type pain, take a few days off from running. Like Achilles tendinitis, if PF is addressed early, you are less likely to see it progressing into a chronic problem.

A night splint that keeps the foot at a 90-degree angle maintains the PF in a stretched position while you sleep. This helps to limit the re-injury that occurs in the morning when you stand up. Try to stretch before getting out of bed.