A reader of the Harvard Health Letter wrote, "I attempt to go into the outdoor pool at my beach club, I gasp for breath, get dizzy and light-headed."
Dr. Thomas Lee, of Partners Healthcare System in Boston, advises the reader: "You're smart to get out of the water when you start feeling winded and woozy."
Lee explains the body responds to cold temperatures -- including those in a swimming pool -- by constricting blood vessels to maintain heat and this can result in angina attacks and heart rhythm irregularities. He also notes cold temperatures could trigger breathlessness due to asthma.
The doctor also points out in the Harvard Health Letter that just walking in water or swimming -- regardless of temperature -- may be placing additional strain on the heart.
Lee tells the reader to have a doctor do a checkup including an electrocardiogram and other tests of heart function. If tests come out fine, the symptoms could indicate an extreme sensitivity to cold, Lee says.