Has anyone controlled or stopped SVT with other exercises like stationary bicycle or power-walking?
Hopefully John, you'll receive other answers than mine.
The phenomenon you're experiencing will perhaps remain a mystery. For some inexplicable reason, cardiac conditioning suppresses your SVT events. At one decade of my life, my early 20's into my early 30's, I was in "world class" condition, literally. I was nationally ranked in skating and sprint cycling, and in just really great condition. However my SVT continued unbridled. It really quashed my efforts to go even farther in the two sports as I would get events at the most inopportune occasions. This was back in the 70's and 80's before electrophysiology procedures were conducted. I had a cardiac catheterization performed in 1971 at Deborah Heart Hospital which was considered "leading edge" at the time. So besides Digitalis based drugs, there wasn't much else that could be done for me at the time. So for me, conditioning did absolutely nothing. I dropped cycling cold turkey after a bad crash in the early 80's and subsequently two surgeries for the injuries I incurred. But I continued skating and coaching up to present day. Interestingly, as I aged into my 50's, my SVT events increased in number, but undoubtedly occurred more at rest than at physical stress levels. My cardiologist thinks this was due to increased PVC rates which occurred at rest more than when my heart was beating in my maximum target zone for my age. He believes that properly timed PVC's initiated my SVT events. Fortunately though, I have some time now to enjoy life without them, and it is wonderful....
John, I too had SVT, specifically born with AVNRT (a type of SVT), but didn't even know exactly what the problem was until about 2-3 months ago, just knew something was not right; I'm 59 now! My SVT events only occurred during my running and cycling, mostly running, and had become much more frequent in recent years. My prolonged high heart rates lasted from about 1 hour to 4.5 hours, but sometimes the only symptom was an abrupt change in my breathing rhythm- a rapid increase from about 145 bpm to 155-160 bpm, with a very inefficient feeling. Sometimes, though that inefficient, labored breathing stopped an soon as I stopped running (no prolonged high HR). It was only after I managed to get to my EP's office, during an SVT event, with a sustained high HR of about 130 BPM, that it was captured on EKG; and SVT (AVNRT) was diagnosed. A recently successful ablation has completely stopped my SVT.
If beta blockers don't help you, then consider asking your doctor about a calcium channel blocker, like Verapamil. Verapamil definitely helped decrease my SVT before I had the ablation procedure done. I have never tried a beta blocker. I am very pleased with the results of my ablation and no longer need Verapamil. Has your Cardiologist ever discussed an ablation procedure with you?
I just remembered having previously read this technique that works for some people to control/stop SVT:
Perhaps your swimming affects you in a similar way to these vagal nerve maneuvers, described at the link above. (One of the ways described there involved " plunging your face into ice cold water").
For those who develop SVT later in life, daily lap-swimming may produce better results than Beta & Calcium Channel blockers:
Description Drugs Daily lap-swimming
Method used to Beta Blockers, or Lap-swimming with
Slow heart rate Calcium Channel snorkel starts at 30 laps
Blockers increase to 60 laps
Resting Heart 72 - 55 72 - 60
Rate at start &
after 2 months
Side affects diarrhea, cramps, none
from Channel headache, hallucinations
Increase in none every month heart gets
heart strength stronger & more efficient
which produces lower
resting heart rate
effects on heart none as there is positive changes in
electric pathways is no change in electric pathways and
and circuits strength or circuits because
efficiency heart becomes
stronger & more efficient as shown by John Wright being
able to manage and
` prevent SVTs by