Medical Specialty >> Cardiology

Doctors Lounge - Cardiology Answers

Back to Cardiology Answers List

If you think you may have a medical emergency, call your doctor or 911 immediately. Doctors Lounge ( does not recommend or endorse any specific tests, physicians, products, procedures, opinions, or other information that may be mentioned on the Site. 

DISCLAIMER: The information provided on is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her physician. Please read our 'Terms and Conditions of Use' carefully before using this site.

Date of last update: 10/20/2017.

Forum Name: Miscellaneous Cardiology Topics

Question: dizziness when exercising

 ifthen - Mon Jun 13, 2005 6:35 pm

Hi, I’m a 39 year old male who has been exercising regularly for about 25 years. I lift weights about 5 times a week and do 20-30 min. of cardio 2 times a week. I eat healthy, don’t smoke and drink a glass of wine a day. I have never experienced any problems, other than normal fatigue, while exercising, regardless of intensity. I’ve been taking supplements such as vitamins and protein powder for years. I have on occasion taken ephedrine (16 mg/day) and DHEA (50 mg/day). I am not on any medications. Overall, my health/fitness is quite good.

In January 2005, I injured my knee and stopped doing leg exercises until after my surgery in March 2005. I started doing light exercises and progressively increased the weight/intensity. One day in May, I completed an intense leg workout (leg presses and squats). Shortly afterwards (5-10 min.) I felt a tingling in both my hands, forearms and feet. I then felt dizzy and felt tingling in my ears and mouth. I collapsed to the floor and was taken to the hospital. A variety of tests were done (ECG, blood, BP, O2, glucose) but everything came back normal. No cause could be found. The dizziness slowly clears on its own after about 2-3 hours.

I returned to the gym, reducing my leg intensity and was able to do several workouts without incident. On June 11, I tried another intense leg workout and once again experienced the same symptoms and collapsed about 5-10 min. after my workout. The same tests were done again at the hospital and nothing was found.

Training other body parts (back, chest, etc.) does not cause this dizziness. Doing cardio, I keep my heart rate between 145-150 bpm without problems. Once I pushed myself to 155-160 bpm and after about 10-15 minutes I felt a little light headed. I slowed down a bit, felt better and no dizziness set in.

Are you able to suggest any possible causes for this? Thank you.
 Shannon Morgan, CMA - Tue Jun 14, 2005 9:55 am

User avatar Your target heart rate is 144. Pushing it to 155-160 is not a good idea unless you do it very gradually. You probably overdid it for your fitness level and didn't get enough oxygen AT THAT TIME. By the time you got it tested by the paramedics, it was normal. Since you are fit, your body resolves quicker. It is also normal for the dizziness to take some time to completely wear off. You said your body functions normally at your normal heart rate, so you more than likely were just working too hard. Rule # 1 in working out: Don't push yourself beyond your limits; it actually burns muscle at that point. Don't forget to have protein and a small amount of good carbs before a workout or your body will turn to glycogen in the muscles again for energy.

If this starts happening at your normal pace, see a doctor.
 ifthen - Tue Jun 14, 2005 7:16 pm

Thank you for the reply. This leaves me with some questions though.

During my workout I rest a couple of minutes between sets, until my breathing has returned to normal. If I was O2 deprived during a set, wouldn’t this rest allow my body to recuperate? When I start to feel dizzy after my workout my breathing has already returned to normal.

Prior to my knee injury last January, I could train my legs has hard as I wanted to without feeling dizzy. At that time, I would only become exhausted during the set, I would rest as usual, and then do another set. At the end of those leg workouts, I never felt dizzy and collapsed like I do now.

I’ve read articles in muscle magazines where bodybuilders have trained so hard that they’ve either thrown up or passed out immediately after an intense set but then seem to recuperate. There was no mention of them feeling ill for hours after their workouts. I have never felt nauseous during my leg workouts.

Is it possible that not training my legs (still trained my upper body) for several months has caused my body to lose some fitness; enough to make me feel dizzy for several hours after my workout? I don’t know what my heart rate is like during a set but I imagine it is high for a brief moment during each set. Both my parents have had heart attacks and I just want to make sure that I don’t have some type health problem too.

Thanks again.
 Shannon Morgan, CMA - Tue Jun 14, 2005 8:51 pm

User avatar It makes sense that the two times you overtrained, the same thing happened. Your vitals, O2, ECG and glucose are all normal. You are simply training too hard for your fitness level at this time.

If you are concerned about heart disease, see a cardiologist for a treadmill test (stress test) and general cardiac workup.
 ifthen - Thu Jul 07, 2005 9:47 am

This dizziness now comes on quicker, even when I lift weights at a moderate pace. After my last episode of dizziness two days ago I still have not fully recovered from its effects. Any moderate physical exertion now such as lifting a 10 litre (4 gallon) water bottle will make me feel somewhat dizzy and I have to lay down. Currently I still feel some slight tingling in my hands and forearms.

I've had numerous tests done since my last posting. They are:
-treadmill stress test
-heart echogram
-chest x-ray
-CT scan of my head
-MRI scan of my head
-neck echogram
-blood and urine tests
All tests have come back normal so far. I am scheduled to have an EEG test done as well as have a 24 hr monitor attached to me.

I recently purchased a fitness heart rate monitor (chest strap and watch) and had it on during my cycling and last weight training. During the cycling, I averaged 145 bpm for 30 min. without any problems. I later lifted some weights with my heart rate not going above 120 bpm and after about 20 min. I collapsed with dizziness. Prior to the ambulance arriving I noticed that twice (about 5 min. apart) that this heart rate monitor dropped to 0 (zero) beats for a fraction of a second and then jumped back up to about 115. At this same time the dizziness became very intense.

If there is nothing physically wrong with me could a virus or bacteria do this? I also eat about 2-3 cans of tuna a day, which is known to sometimes have traces of mercury in it, but other than the dizziness, I don't think I have any of the other symptoms of mercury poisoning.

On July 8 after eating breakfast and not doing anything physical, I had another episode. My chest area felt different (no pain), my hands and forearms tingled and cramped up a bit and I felt dizzy again. I am now hooked up to a 24 hr heart monitor.

My family doctor as well as the doctors that I've seen at the hospital are all baffled by my condition. Do you have any further suggestions? Thank you very much.
 barbeauj - Mon Jul 11, 2005 12:39 pm

Hi ifthen,

I would not worry to much about your heart rate monitor dropping to zero. This may happen if there is some interference around (other HRM, cell phones, electric equipments, static electricity etc). Sometimes when the chest belt is not well adjusted it can slip and cause a false reading on your HRM (0 or irregular heart beat). Try not to worry to much as this can cause stress and weird feelings during exercises.
 ifthen - Wed Aug 10, 2005 8:00 pm

As it turns out, the cause of my illness appears to be mercury poisoning. Specifically, the lab indicated that a normal range for mercury should be 0.0 – 18.0 nmol/L and mine came back as 32.4 nmol/L.. All my other tests have come back normal.

Thanks to those who replied to my previous posts.
 mpow - Fri Aug 19, 2005 12:23 am

Thank you for reading this. Please offer me some insights.

I am 30 years old 5’10 222 lbs. I have recently begun a strict workout and eating routine. I have done a similar routine twice before once in 2002 and once 6 months ago. The strict routine both times lasted about 7 weeks. Each time the results were phenomenal. A body transformation, and mentally feeling great.

I basically follow Bill Phillips “body for life “ Program. It involves 3 days of Cardio and 3 days of weight. The Cardio days are only 20 minutes and consists of 1-minute intervals going from 60% exhaustion to 90 % exhaustion, and then climaxing at 100% exhaustion. So the idea is pretty much to push yourself toward exhaustion. The weight training is a 45 minute work out where you weight train at a some-what rapid pace to keep your heart rate up.

Anyway in these types of routines I have always gotten somewhat shortness of breath, minor chest pains and a bit of dizziness. But as the weeks went on working out became more natural and those symptoms would subside.

Other pertinent facts I never have smoked, I used to drink alcohol a couple times a week but when I did it was more than a few drinks sometimes 3-11 drinks in a night sometimes

I have had some episode a few months ago and 5 years ago, that were typical panic attack symptoms (shortness, sweats, dizziness, feeling of heart attack, chest pains, numbness, skewed reality thought process etc…) both times hospital said vitals were fine. My doctor both times prescribed Anti-Depressants to treat anxiety. I would take them in low dosage for about six weeks and then go off them because they make me lazy and sometime depressed.

The first episode, 5 years ago I had the EKG test, it can back fine. This last episode, a few months ago, I had want to get some tests done to relieve my worries but my doctor talked me out of it. He said he would order them if I really wanted them. But he felt very confident after his examination they would come back fine. He said it was anxiety. Although I did have blood work done and no problems showed up.

Anyway those are of the preliminary facts, so now to the issue, I recently began this strict eating and work out program again. I try to eat 5-6 times a day. A good protein and carb with each serving (so lots of canned tuna, cottage cheese, fruit, and MYPLEX shake meal replacements)

I have also switched the work out routine to a circuit-training program. For 30 minutes I alternate in 30 seconds intervals between cardio and weights, with a 15 second rest between them. I plan on doing this 3 –4 days a weeks and then 1 or 2 other days I will do a 20-minute cardio work out. Overall I will probably get 5 days a week in. I am switching to this circuit program because on 3 days of weighs and 3 days of cardio, I get pretty muscley and although I feel great and look great I don’t really lose that much weight. It ‘s like my fat is replaced by lean muscle mass. Anyway I think I need to reduce my overall weight, so I am trying a program that will not put so-much muscle on me.

Anyway as I was doing my 30 minute circuit training work out, I got a feeling of fatigue sometimes, some dizziness, then I will get pretty hot and sometimes sweat quite profusely, I will get small little chest pains, I used to just work through these cause the doctors always told me I had nothing to worry about. Anyway now I am more concerned because on more than a few occasions I had stop and calm my self down. The fatigue, dizziness or sudden overheating would cause me concern so I would settle down. During these circuit training sessions this usually happen in the Cardio intervals. Also when I was doing 3 days of weights and 3 days of cardio. I would sometime get the sudden overheating, and the dizziness on the cardio days, especially when running on the treadmill. But I would not really get them on the weight training days also I would not get them on lower impact cardio machines like the bike.

The last few nights I have felt quite bad at the end of my work out. It’s like I have to sit before I can walk out of the club and sit even longer before I can feel comfortable driving home. Then for about 1 to 2 hours, once I’m home I feel like I need to be cautious with my activity (i.e. walking upstairs). I still don’t feel right . But after this period, I feel very fit and mentally good. The next morning I always wake up feeling very fit. Hence, why I am so reluctant to abandon my commitment to this strict regimen.

Other facts I do try to get my heart rate going to burn calories. I noticed I got it up to 185 for a few minutes. Is that bad????? The machine even said 205 for a couple minutes but I’m not certain that was accurate because I was not holding the metal handles. It seem to be using a formula of based my weight, age, and resistance level. But even using that formula, a machine saying 205 BPM is that bad????

Mediation and supplements:
When I workout on my routine I use Creatine. I use less than the recommended dosage. I am currently weaning myself off Lexipro, which I was taking to control my anxiety issues. I took it for about 2 months. But like I said earlier it makes me lazy and kind of depressed.
When I am on my work out routine I drink about 80 to 130 ounces of water a day.

I go back forth with caffeine at some point I drink 2 diet mountain dews or 2 coffees a day. Other times I will cut caffeine out completely or use it in small doses.

I do feel I should mention at certain phase of my life in the past I used caffeine in excess of 2 drinks a day greater than 3 time a week.

Other pertinent facts
I feel like I‘m in bad shape, hence why getting back on my strict routine. Any moderately exercise outside in Carolina humidity brings on the same symptoms. For instance I took a ¼ mile walk from one office to another on a hot humid day in professional dress attire. Anyway on the way back, I had to squat down on the sidewalk to rest for a minute then I had to get into the closest business sit in the a/c, and drink water for 10 minutes. I am only 30 years old I don’t feel these problems are normal. What do U think is wrong with me????

Do u think I may have some type of heart condition. A similar post on this turn out to mercury poisoning from to much tuna fish. Could something like that be possible? I really need to continue my work out regimen to get back to feeling good. I know there is a lot in this post, but I just want to give you all the facts.

To sum up I am really concerned with my dizziness during and slightly after my workouts. Also concerned with the other symptoms such sudden overheating, generous sweating, shortness of breath and slight chest pains (although they don’t worry me as much cause I have these when I ran for the past 10 years, doc would say it must be a pulled muscle or something because my test would come back ok, and when I elevated my heart rate in other activity there was never a chest pain) but now I get those chest pains in other activities such as swimming or surfing on a hot humid day.

Although a month ago I went mountain biking for six hours and was fine, although the girl I was with did say I sweating really bad. That was also in the mountains, which is much less humid climate. That brings to light another issue, it seems to be less noticeable in less humid climates like when I lived in Colorado or when I run here in the winter.

I mentioned surfing earlier I have surfed for 15 years and now I don’t much anymore because I don’t feel I have the energy or that I am not in the shape to do it. I have gone out a few times but sometimes I get the symptoms I describe above, so I get scared and feel I have to stop.

Anyway what do think this???????? Please help I feel handcuff.

Thank you so much for your time, energy and efforts

| Check a doctor's response to similar questions

Are you a Doctor, Pharmacist, PA or a Nurse?

Join the Doctors Lounge online medical community

  • Editorial activities: Publish, peer review, edit online articles.

  • Ask a Doctor Teams: Respond to patient questions and discuss challenging presentations with other members.

Doctors Lounge Membership Application

Tools & Services: Follow DoctorsLounge on Twitter Follow us on Twitter | RSS News | Newsletter | Contact us