Tri-training

Yesterday, Sunday, worked on elliptical for 40 minutes.
It was good but felt a little dizzy.

This morning I went in for a strength training and abs class.
This too, felt great, but during certain moves felt dizzy.

I know I am breathing properly and such so I asked my hubby what he thought.
I have always had low blood pressure even through pregnancies, so John's thought is that my blood pressure needs to be checked.
I wonder if those machines that I used to play with growing up are still around at the super market?