Big H

During a race a friend of mine cramped. Another cyclists stopped and gave him a Rennie. With indignation he said he cramped and did not have heartburn, The other guy insisted, he took the Rennie and Viola!!!!!! the cramp was gone. Could there be any truth in this, will Rennie (only one ) have the capacity to reduce lactic acid???? This was related to me as true and it is NOT a joke!!!

Keep those wheels spinning

Big H

demoncyclist

What exactly is a Rennie???

DEMON

Big H

Sorry... I forgot we live in DARKEST Africa!!!!!! I assumed Rennies is a worldwide brand. Rennies is a antacid tablet used to counter excessive stomach acids and also helps for heartburn. Hope this helps.

Big H

keithnordstrom

hrm what's in it?

Richard D

From memory, largely calcium.

cbhungry

I wonder if its calcium carbonate or calcium citrate. I suspect the former, only because it is cheaper. Low calcium causes neuromuscular irritability and cramps but usually the main mechanism of cramping after sustained excercise is from low magnesium or potassium.

Perhaps the carbonate in the rennie provides a good base buffer but physiologically, one tablet and its absorption should not affect the lactic acid buildup. Bicarbonate, specifically sodium bicarbonate is an alkalising agent and therefore reduces the acidity of the blood (known as a buffering action). However, the clinical research I've seen that showed any improvement in lactate threshold involved loading up with 4grams/day of sodium bicarbonate for six days before it was able to improve VO2max by 9% and the Lactate Threshold raised by 12% .

Not sure why the rennie would work so fast. Did you or he consume something else with it?

nhorscro

I thought cramps were predominantly caused by electrolyte loss, not lactic acid build up? Those are two different things I believe. For instance, I can cramp on a long ride (50+ miles) of low intensity (Zone 1 and 2) if it is a hot day. Using a HRM I know I am riding aerobically 95% of the time so lactic acid build up is not an issue.

The loss of cations such as Na+, Ca++ and Mg++ are what usually cause cramp, and the Ca in an antacid help some people fight off cramp. For instance I know my cramps are caused by Ca loss or deficiency so when I start cramping I take either a Citracal (calcium citrate) or an antacid (calcium carbonate) and I usually get some relief in 5 minutes or less.

So in this case the calcium has nothing to do with VO2 max, LT or any performance related parameter. It is a simple replacement of divalent cation lost during strenuous exercise that probably induced a lot of sweating.

cbhungry

Although bicarbonate loading at the above loading dose over 6 days or immediate preexcercise dosing does improve the vo2 max, lactate threshold etc. according to many field tests and clinical trials. https://www.asep.com/supplements/cont...tes.cfm?sid=28

So the one rennie wasn't enough to provide this buffering except a small amount of calcium repletion. His friend must have heard about the bicarbonate studies and attribute the calcium carbonate as a possible base buffer.

Lambert Fick

It's the ingredients that's the same, that is required for spasms and cramp relief due to deydration and medical conditions, it's just better at it, and cost-effective and in a compact size. I came across the article because I am trying to reverse engineer as to why it works better than Malaria meds, Vitamin D and K and other magnesium combinations and supplements for cramping.

Carbonfiberboy 

No, cramps aren't caused by low electrolytes, and yes the Rennie is probably a cousin to our Tums, which helps with cramps, and in this case as in all cases of cramp remedies which work, it's the taste, only the taste, nothing to do with the ingredients. Pickle juice is another remedy which works. Cramps also have nothing to do with dehydration, it's just muscular over-work, i.e. you haven't trained hard enough to what you're attempting. The forgoing is for cramps during. For cramps after, it's pretty idiosyncratic, except that the same remedies work for cramps after as for cramps during.

Iride01 

21 years later than this thread, some find that pickle juice helps interrupt cramping or prevent it. I've been pretty good at just acclimating myself to the exertion required for the task and the temperatures involved. So I've never had the reason to try any.