More conflicting data on caffeine and exercise - this bad

yeahright

yeahright

Well-known member
Awards
1
  • Established
NETSCAPE NEWS BULLETIN

If you're planning to exercise later today, make sure you stay away from beverages containing caffeine.

Drinking just two cups of coffee before exercise decreases blood flow to the heart while you're working out, and this reduction is most pronounced at high altitudes, reports Reuters of new research from University Hospital Zurich.

Healthy people may be able to tolerate the reduced blood flow, but it could be especially harmful to anyone with coronary artery disease.

The study: Led by Dr. Philipp A. Kaufmann, the team used young, healthy adult volunteers to test the effect caffeine had on blood flow to the heart both at rest and after exercise. They ran the tests at normal oxygen levels and then simulated the low oxygen levels that occur at high altitudes. Cardiac blood flow was measured at a baseline and then 50 minutes after the volunteers ingested 200mg of caffeine, which is about the equivalent of two cups of caffeinated coffee.

The results: At normal oxygen levels, caffeine had no effect on resting myocardial blood flow, but at low-oxygen levels, resting myocardial blood flow was significantly increased by caffeine. However, during exercise, caffeine caused a significant decrease in blood flow to the heart at normal and low oxygen levels. Specifically, caffeine caused the myocardial flow reserve to drop off 22 percent at normal oxygen levels and 39 percent at low oxygen levels, reports Reuters.

The takeaway: Skip the caffeine before you get on the treadmill.

The study findings were published in the Journal of the American College of Cardiology.
 
LakeMountD

LakeMountD

Doctor Science
Awards
1
  • Established
Yeah it is pretty well known that it is a vasorestrictor. I always notice shortness of breathe when I use caffeine, although I don't really mind because I don't do cardio :).
 
bioman

bioman

Well-known member
Awards
1
  • Established
lol

As I read this while drinking coffee, after just dosing my clen, and preparing for some cardio at 7,000' elevation.
 

rocketscientist

Registered User
Awards
0
That may be so, but that's just one of the effects of caffine. I think however that the effect of caffine as a stimulant leads to an overall increase in output... but as the study mentiones may be risky for some.
 
bioman

bioman

Well-known member
Awards
1
  • Established
One may be able to offset the cardio-vasoconstriction effects by adding in some kind of arginine? It would be nice to see a study look into that.
 
jmh80

jmh80

Well-known member
Awards
1
  • Established
Bio - they give nitroglycerine to heart attack victims for a reason....

I suppose it would be a bit of a waste for the arginine (but if you use regular arg. it really isn't that expensive).
 
bioman

bioman

Well-known member
Awards
1
  • Established
That's what I was thinking. I use DiArg Malate.
 
jmh80

jmh80

Well-known member
Awards
1
  • Established
That would be a bit more of a "loss" if you will because it's more expensive.

I've had to start taking 5 grams of base arginine to combat the BP increases of TST/TRN.
 

Similar threads


Top