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Ann G
04-11-2007, 02:46 PM
Hi, I just registered here. I've been an avid cyclist for the last 4 years, and went on RAGBRAI all of those years. I've been aware that cyclists and swimmers have the worst bone density for awhile, but I managed to lie to myself about that until recently. (I told myself that the problem was restricting exercize to cycling, and not engaging in strength training and weight bearing exercize.) From what I've read lately, it's really the cycling itself. The problem is that you lose calcium through sweat while engaging in exercize that is not a weight bearing exercize. The calcium leaches right out of the bones. I'm already on meds (evista) for low bone density, even though I walk (every day during fall, winter, and spring, but I'll admit, less often during the summer) and use weight machines at the Y (usually twice a week). I've considered quitting cycling because of the bone density issue, but lately I've been reading about some sports drinks that contain calcium (along with other electrolytes lost through sweat). Up until now I've just put water in the bottles on the bike, and try to have at least 2 servings of dairy products per day. Okay, I should probably increase it to 3 per day, but that doesn't solve the problem of what to put in the water bottles. Right now I'm looking at some products that contain calcium in with the mix, like Ultima Replenisher. One thing I like about it is that it's available in single-serving packets, so would be easier to deal with on a bike. Is anybody else concerned about this issue, and have you come up with a solution?

Aint Doody
04-11-2007, 03:28 PM
That's really interesting. I'd be interested to know all the sports drinks containing calcium. I have a friend (male) who sweats profusely and loads up on Tums before he rides to prevent muscle cramps. I never thought about bone loss.

Ann G
04-11-2007, 03:57 PM
Here is a site that has a chart with several different sports drinks and various ingredients that they contain. I didn't see Propel on here, but there is a Propel Calcium Fitness water too.

http://www.eload.net/eProductChart1.htm

sarahlou
04-11-2007, 04:32 PM
All of our bodies minerals are lost through sweat (and urine) so you need to keep up on minerals daily. And in order to absorb calcium, you need vitamin D- the two go hand in hand. So if you're worried about calcium, also look at vitamin D intake.

mimitabby
04-11-2007, 04:32 PM
I found this from 1950:

Perspiration as a Factor Influencing the Requirement for Calcium and Iron
Frances A. Johnston, Thelma J. McMillan and Erica R. Evans

The College of Home Economics and the School of Nutrition, Cornell University, Ithaca, New York

Perspiration was collected from 4 young women, each of whom served as a subject for 4 periods of approximately an hour each. The temperatures used were 97°F. dry bulb and 93°F. wet bulb. The collection was made in enamel tubs in which the subjects sat during the sweating period. Perspiration from all parts of the body except the scalp was collected.

The mean loss of body-weight per hour during the collection periods was 10.87 ounces (308 gm). The mean loss of iron per kilogram of body-weight loss for each of the 4 subjects was 0.24, 0.26, 0.26, and 0.28 mg; the mean loss per hour was 0.48, 0.063, 0.080 and 0.108 mg. The mean loss of calcium per kilogram of body-weight loss for each of the 4 subjects was 13.42, 30.42, 32.52 and 40.10 mg; the mean loss per hour was 4.17, 6.80, 8.84 and 14.33 mg.

The administration of 25 mg of iron with breakfast on the day of the collection did not increase the loss of iron, nor did a subject who was taking iron therapy daily secrete more iron than the other subjects.


okay, they were losing almost 11 ounces of body weight AN HOUR and losing about 30 milligrams of calcium an hour.
If you are taking your 1000 mg of Calcium a day; you are COVERED. and ALL exercise will do this to you, but since Bicycling doesn't "weight bear" it doesn't rebuild what you lose

Ann G
04-11-2007, 05:27 PM
1250 mg, but I'm still on evista for low bone density. I've been seriously considering quitting cycling, but since it's my favorite form of exercise, I'm looking for alternatives. It would be nice to think that since I'm taking extra calcium I don't need to worry about this, but somehow I don't think it's working that way.

mimitabby
04-11-2007, 05:34 PM
Ann, I am in the same boat as you. I started doing weigh bearing exercises as well for Osteo. I do 10 minutes of stairs 4-5 times a week, I walk a mile a day; if you can run that's even better. I also am lifting weights under the guidance of a trainer with bone building in mind.
I believe that if it wasn't for bicycling, i would never have the strength or stick to it iveness to do any of this stuff, so don't give up cycling, just augment it.

silver
04-11-2007, 07:35 PM
1250 mg, but I'm still on evista for low bone density. I've been seriously considering quitting cycling, but since it's my favorite form of exercise, I'm looking for alternatives. It would be nice to think that since I'm taking extra calcium I don't need to worry about this, but somehow I don't think it's working that way.

Cycling is my favorite! I got into exercise running, then broke both my feet one at a time, so I got a bike.

So, the answer is TRIATHLON!!!! ;) You get to ride, and you are forced to run and swim (or that's how I look at it) and it's fun! Give it a thought!

Thorn
04-12-2007, 05:32 AM
Yep...I think there is something healthy to the triathlon suggestion. After my DH read an article that said that an otherwise healthy young female cyclist was tested with a bone density of an 60 year old, I started to question my cycling, too.

Prior to finding bicycling again, we did a lot of walking and hiking. But, walking isn't aerobic enough anymore. Also, DH (he is a voracious reader) found an article that claimed walking by itself may not be enough--it is the stress of and variety of the exercise that builds bone mass. This is the same reason they say to peroidically change your weight routines if you're trying for bone density. Some articles were recommending weight vests for walking to increase the stress.

For me, besides putting more calcium in my diet, I've realized I guess I have to put some running into my routine. I don't want to give up riding (I so prefer it) so I'm planning on adding a "brick" as the triathlon gals call it to shorter rides. That is, after i come back, adding a short, 1 mile run. One mile seems to be a minimum that is often suggested, but I remember what those runs after rides felt like--uuufff....that should be a stress.

If anyone has some good solid references/recommendations on this, I'd love to read them. It seems like the issue of hormone replacement therapy that we are the generation that will be experimented on.

NJ Jess
04-12-2007, 06:10 AM
Yes, I know it sounds strange, but it works. As does simply jumping 10 times appr 4 times per day. Reason: a bodies mechanism that tells the body to build stronger bones are its GROWTH PLATES. They are the special bone cells located in the center of the femur (between the knee and hip joint).

When a person runs, jumps, lifts weights,..their femur "feels" the amount of stress its under. If the stress is high, frequent, intense,....your growth plates tell the bone cells to increase intake of Calcium, Phos, Vit D, Mg, and boron. The average American diet does not have enough nutrients to sustain a highly athletic person. Poor soil and highly processed foods greatly reduce nutrient content of foods also.

Suggestion:
Jump up and down with your body weight 10 times 4 times per day. (if you are heavy, do this in the pool..water waist deep. Practice proper jumping form,....believe it or not,....I bet your body forgot how to do this,..really.)

Suggestion:
Continue to take Multivitamins,...and a MULTIMINERAL,...but not at the same time. I take my vitamins with breakfast. I take a multimineral and a TRACE mineral supplement with dinner. Minerals for bones are best taken before rest /Bed. They help you sleep, eliminate restless leg syndrome, cramps, and actually build more bone structure at night. (Do you remember,...your kids growing pains at night?)

Suggestion:
Drink chocolate milk after you exercise to increase glucogen stores and nutrients. During exercise, I have a water bottle with 1/2 cup Vit D fortified Orange juice, 1/2 tsp sea salt, 1 TBsp POWDERED gatorade, 2 TBsp lemonjuice. Please pass this info to your heavy sweater friend. He your greatly benefit by also having one can of regular soup the day before he rides. Under intense exercise, the body dumps sodium in the first hour and a half. After that, the body tries to conserve it's sodium for proper heart function. Therefore the body tries to "stop" you from moving by cramping. If you truely ride hard, drink fluids the prior 2 days of the ride and have some sodium. Then have a 1/2 tsp in your waterbottle mix to replenish for my endurance/epic rides.

Good Luck, God Bless

Offthegrid
04-12-2007, 07:35 AM
You could also use nuun (http://www.nuun.com/nuunis/science.html) as an electrolyte replacement. It has some calcium in it along with other minerals.

I plan to use this as soon as it gets warmer than 30 degrees because I sweat a LOT.

mimitabby
04-12-2007, 07:46 AM
Hey NJ, thanks I will start jumping! great idea!

Ann G
04-14-2007, 07:43 AM
Thanks for the jump rope idea. I've also read that chocolate milk is a good high-calcium energy drink, besides being tasty, so I'm going to add that to my daily routine.:)

KnottedYet
04-14-2007, 07:54 AM
When I was a kid I jump-roped all the time! Now just jumping 10 times in a row is tough. Jeeez!!!

Knot-needs-a-grown-up-jumprope

KnottedYet
04-14-2007, 07:55 AM
When I was a kid I jump-roped all the time! Now just jumping 10 times in a row is tough. Jeeez!!!

Knot-needs-a-grown-up-jumprope

Jumping form: be sure to keep your knees apart. don't let them collapse inward!

yellow
04-14-2007, 06:38 PM
Mimi, that tidbit from the 50s was interesting. I flunked my iron test a few weeks back (hemoglobin 11, so not a horrible flunk, but a flunk nonetheless) and the doc thinks it's exercise induced anemia. I'd never heard of it before (from the lit she gave me, about running and XC skiing, both of which I do a lot of: "The forces exerted on the red blood cells in the capillaries of the feet may rupture the blood cells and lead to anemia." Whoda thunk it??) She gave me some stuff to read and put me on a liquid iron supplement.

I also had a bone density wake up call a few years back...led me to drastically change my eating habits. I recently started using those calcium chews at the suggestion of my doc (fruit flavored, of course). A little sugar in them but not bad. I also lift weights and run, so I'm doing what I can.

mimitabby
04-14-2007, 06:40 PM
Yellow, sounds good. I haven't seen any fruit flavored calcium chews; what are they called? We all have to do what we can do.

Recently, my DH had his annual exam, and they took blood very shortly after one of his 200 k rides. THere were some abnormalities that his doctor explained away by saying that he had had some extreme exercise a few days away.
THis included low white blood cells and cloudy urine!

yellow
04-14-2007, 06:51 PM
Recently, my DH had his annual exam, and they took blood very shortly after one of his 200 k rides. THere were some abnormalities that his doctor explained away by saying that he had had some extreme exercise a few days away.
THis included low white blood cells and cloudy urine!
I have flunked urine tests many times due to the whole exercise thing. Comes back as some sort of an indicator of renal failure. Very common, apparently.

Oh! The calcium chews were something I just got at Fred Meyer aka Smith's in Utah (just the Kroger/FM/SMith's brand). They were by the calcium supplements in the vitamin aisle.

mimitabby
04-14-2007, 06:52 PM
! ! ! ! !

no kidding.

Ann G
04-20-2007, 05:16 AM
Viactiv also makes a calcium chew with 500 mg of calcium, plus vitamin D and K. They come in 5 different flavors, and I've been using the milk chocolate flavor.