“Why when you do strenuous exercise, usually cardiovascular, sometimes you feel nauseous, dizzy or even vomit afterwards?
I have been doing Cardio in the last couple of months 5 times a week for 40 minutes and regard myself as fit.
I have stopped my exercise regime during my 2 week holiday and after returning to the gym, I’ve experienced the above symptoms.
Is it possible that I lost my fitness?”
During normal resting conditions, your body’s tissues, particularly your muscles, are utilising their energy requirements from the breakdown of fat, and to a lesser extent, from circulating glucose in the blood. Upon initiation of strenuous activity, the rapidly metabolising muscle tissue needs to switch over to using predominately glucose. This comes from both their inbuilt glycogen reserves, as well as from the liver’s stores of glycogen. This switch can take several minutes. In an unclimatised individual, if blood glucose falls too rapidly before it can be replenished, the symptoms you described may become evident.
It is indeed very possible to “lose fitness”. Your heart decreases back to normal size after only several weeks, and needs to be built up again before it can reach its previous efficiency. Additionally, changes in the muscles themselves, relating to how efficiently they use energy to carry out contractions occur with regular exercise. These are reversed upon exercise cessation.
What I’d recommend, is taking a more prolonged warm up period. Something as simple as walking briskly for 10 minutes, will cause the required shift in metabolism, allowing your energy supply mechanisms to cope with the increase in demand.. Don’t just suddenly begin at your jogging pace. Also, ensure you’ve eaten something relatively high GI 25-30 minutes before your session. This should be light and easily digestible. Try a banana, or even a chocolate (you’re allowed to since its about to be put to good work). Other fruits work too. Additionally, a coffee will naturally up your heart rate and blood pressure, prepping you for work. Give yourself time, and within several sessions, you’ll be feeling more like you used to. Although fitness is lost, it is also regained a lot quicker in previously fit individuals. Good luck!