why does my body itch during running exercise?

Sounds like prickly heat to me. Try losing some layers during your workouts.

I have the same exact problem - and I can't find the answer either!  my skin turns red and seems to swell a tad, then i can't stop itching and it sucks.  It seems to be worse if it's cold outside.  Plus, it happens to my arms sometimes when riding a bike outside on a bumpy road.  I used to think it was because I was 10 pounds overweight, but then I went through a period when I was extremely thin and it still happened. 

OMG!!!!!!!!!!!  I love you people and I love the internet!  Thank you so much for letting me know that it's not just me.  I have a life-long history of running.  I ran very competetively in high school, college and professionally.  In those days I worked out 6 days a week and the longest break I ever took from age 16-24 was about 3 weeks.  I remember experiencing the itching maybe twice in high school and about 3 times in college.  It was EXCRUCIATING and had me wondering whether this was some bizarre psycho-somatic response deeply rooted in the repressed trauma of all of the extreme training I had endured since adolescence (even though I always loved running with a passion)!  Or maybe an undiagnosed allergic response.  I really had no clue.

I stopped competing about a decade ago and nowadays, it happens just about every time I attempt to walk or run outside for a prolonged period.  And, yes, it get worse if you scratch or even just bearly graze your skin.  It's unbearable.  I must say, it does seem to happen more often in winter but doesn't happen when I run on the treadmill indoors.  Go figure!

I found the answer on another website.  I'm so excited!  This condition has prevented me from working out for so long - it's terrible. 

You have to take an antihistimine... It stops your skin from itching when you have an allergic reaction.  You know how you get extra itchy when you have an allergic reaction to something.  I'm assuming something like a non-drowsy Benedryl or something equal would work.   

My itching/scratching episodes would begin as early as 1/4 of a mile and I am in my 30s.  It has been terrible but since I've been taking hydroxizine (for itching) I haven't had an episode yet!  My doctor prescribed hydroxizone for me some time ago and when I saw the advice to take it on a website...I thought  - I have some allergy pills left and decided to try it and it's working!  The itching when walking or running definitely isn't an allergy but it the allergy medication does cure the itching.  I guess its because you do itch like crazy when having an allergic reaction to something and the antihistimine stops the itching.  I've tried everything else so I thought I'd try it and it worked the very first time. 

I have been dealing with this condition for some years now.  I can't believe it.    I was actually back on line looking for the site where I found the info to let everyone know it worked.  I found this in my search for the site and wanted to let you all know.  It really works!  You have to try it... believe me.

Here is another possible cause . The cure, consistancy.

"Itchy skin usually occurs during exercise performed after a long period of inactivity. The itching is not on the skin, it's inside the actual limbs. There are millions of tiny capillaries and arteries inside our muscles which expand rapidly due to the demand for more blood that is brought on by exercise. When fit, these capillaries remain open allowing maximum blood passage, but when unfit and inactive they tend to collapse, allowing only minimal blood passage (which is sufficient for a sedentary person however). The rapid expansion of these vessels causes adjacent nerves to send impulses back to the brain which are interpreted as an itch. That's why after a few sessions the sensation tends to go away. Just another indication of increasing fitness levels."

I started having this in college whenever I would workout or walk outside briskly, especially in the winter. It took nearly 7 years to diagnose and most of it I had to do on my own through trial and error. I had never had an allergy before at all and I loved to workout. I went to many doctors who were completely stumped by it. One doctor, once he found out I was an MDiv student at a seminary, even told me that I "God was giving this to me to teach me something." I couldn't believe I had to pay the co-pay for that! Finally, I started taking benedryl prior to a workout, and it worked, but made me very sleepy, so I had to start running at night so I could sleep afterward. I didnt like this, so I finally found a new doctor and took him all my findings and he diagnosed me with an exercise allergy that manifests in itchy legs and feet, which then moves to my torso, neck and arms over time. He put me on Zyrtek and I've been using that ever since. That was 7 years ago, and I only have trouble if I forget to take my Zyrtek for 2 days or more. I've been able to workout and even have a personal trainer now. 

I have always been an athlete, but this is something I have experienced my entire life, ESPECIALLY when I go running.  At a young age, my father told me that I was just out of shape and needed to invest time (and severe itch) into getting my body ready for working out.  Once I put the effort out, the itch began to go away, and I soon became one of the best high school runners in the state and was nationally ranked in college.  However, if I take time off, I am right back to square one, where I look as though I've never worked out before. 

Might I suggest a drug-free method of working your way up to long distances.  Run a quarter mile today, half mile tomorrow, etc.  I feel that when I take long breaks from working out, I have to do this in order to get rid of the itch.  Usually within a week of consistent running, the itch goes away.  This is something I would recommend to anyone with this problem, because this has, and will forever, torment me. 

Perhaps, however, you can avoid the itch all-together by taking the antihistimene until the body is in shape, then get off of it.  What I was excited about was that this didn't stop me from achieving my fitness goals, so YOU CAN BEAT IT.

I have had this problem for years and finally went to a doctor and got prescribed allegra which is a non drowsy antihistamine. I take it 60 min before exercise and it works. It is an allergic reaction. I notice in the winter when it is extremely cold sometimes the allegra doesn't cut it and I have to forget exercise all together. I also have to moisturize before I exercise and that helps too. It's weird. I thought I was the only one in the world. My friends laugh when I say I am allergic to exercise but nyone who has experienced this knows it is EXCRUCIATING!!!!!

so i wasnt the only one struggling with this. i had to buy an ipod and then blast the music just to get distracted. when i am able to ignore the initial statges, it goes away after 15mins on the treadmill. i also recomend taking a quick shower before exercising.

I have the same problem. I just tried to work out a few minutes and the itching sensation just jolted into my body. This sucks really bad. The itching is mostly on my chest,stomach,abs, and back big time!

Oh geez! I get that too. Abs, butt, thighs, arms. I was always too embarrassed to ask anyone if thats normal. I believe it's the vibration that causes it. The only way to stop it is to force yourself to NOT itch it. It will feel like your skin is on FIRE! But it will calm after a few minutes. I've never been able to keep running though, I always have to stop and do something else or it will come back. That must be really embarrassing during outside sports. I do all my routines at home. I wonder if there is a creme you could apply before hand that would calm it a little.

i seriously thought i was the only person with this problem!  I didn't even know what to type in the computer and I am so glad I am not alone.  I love exersice and do martial arts but when i do too much repetative movement i feel like i have fire ants all over me!

I have the same problem. When I dont run for 2 days or more, the itching usually starts 10min into the run. It starts either on my hips or legs, very random, then eventually the entire body. I tried many things, as said earlier, the key is to constantly exercise. Or take an antihistamine (over the counter is fine like zyrtec or claritin, which ever one works with your body), personally zyrtec is wonderfull, according to my allergist, it stays in the skin for 5 days!.  If you don't like to be on drugs all the time, just take the antihistamine when you start running again, and once you get consitent, go off the pill. Works for me. Hope this helps :)

okay I have the answer for you all you must go see you doctor I thing you all have liver problem and you not drnking to much water I know I have the same problem

dont drink coffee for tow weeks or  alcohol and have some chick peas and radish

that will take oil from your liver. in one week or tow you will see diffrent just try it

will work.

ps. please do not take hot shower

    thank you bj

Wow! I have this same problem. It drives me INSANE! I feel like I'm going to collapse from the itching alone. My itching is definately not on my skin, it is inside where no amount of scratching can reach. I have to slow way down to get it to stop. I do not excersise often, but when I do, I probably over do it. I have only noticed this when running or high aerobic activity, even on a treadmill. Also, I'm a smoker, and I am pretty sure my circulation isn't the greatest. the previous answer about this being inside the limbs and a reaction to inactivity is spot on. I'm going to try benedryl becuase I don't want to give up. Where there is a will, there has to be a way! Thank you all for having the same unpleasant problem! If not for you, i'd be overwhelmingly frusterated with this extremely uncomfortable issue!!!

got this from another site...

I experienced this to the point that I could not continue my run so I did a little reasearch. It usually occurs during exercise performed after a long period of inactivity. The itching is not on the skin, it’s inside the actual limbs. There are millions of tiny capillaries and arteries inside our muscles which expand rapidly due to the demand for more blood that is brought on by exercise. When fit, these capillaries remain open allowing maximum blood passage, but when unfit and inactive they tend to collapse, allowing only minimal blood passage (which is sufficient for a sedentary person however). The rapid expansion of these vessels causes adjacent nerves to send impulses back to the brain which are interpreted as an itch. That’s why after a few sessions the sensation tends to go away. Just another indication of increasing fitness levels.

Doctor tells me it may well be Amalgam Filling causing the itching, it contains small percentage of mercury.

Oh well, I have a blood test tomorrow and dentist check up so lets see what is the real problem.

If not solved, then plan b will be run run run and sweat sweat sweat fight the battle and hope it goes away.

Will update when I find out the answer to this cause its also annoying me.

I told my husband my fat itches when I run. He made fun of me! I am so happy it isnt only me! BTW has anyone noticed it is more the "fatty" places in your body that itch?

I am not overweight by any means but I feel like its the parts of my body which have a higher percent of fat that itch like my inner thighs and love handle areas!

I have allergies so I usually take Benedryl or smthg like that...still happens but not everytime I run only when I havnt for a while.

Also, since I was little I always cured an itch (like an insect bite) with alcohol (not the drink but rubbing alcohol). At my gym they have hand sanitizers in the bathroom so when I itch I go in to the bathroom and runb sanitizer where it is itching. Cures the itch immediatly and ppl just look at me like I am crazy putting alcohol on my red (and I mean bloody red) legs!