Light in the head

I am currently doing my placement in RPH-SPC, Neurology Outpatient. Every Thursday, we assist our supervisor in conducting a running group for patients who have had neurological conditions.

The patient I was supervising had a stroke 2-3 yrs ago and had already done his warm ups (consisting of step up 5x and walking approx 200-300m to the main gym), we then got him on the ex bike to build up his ex tolerance. After the 9th min, he complained of light headedness and I had to ask another colleague to help me get him off the bike and take a seat.

She then promptly went to get him a cup of water and instructed him to take sips from the cup and not to gulp it down. After 2-3mins, my supervisor came, asked how he felt and proceeded to take his pulse rate (which was normal) and cos she could feel his pulse rate well assumed his blood pressure was not low.

When my patient felt lightheaded, I felt it too cos I panicked and did not think of the normal protocol that I should have done ie: take PR, BR etc. Thinking back, I should have asked the patient if he had a meal before he commenced exs, as according to my colleague, that cld have led to him feeling lightheaded (low blood sugar). Although he did comment that this was his first time on the bike after a christmas and new year break. Could this have led to a further deterioration in ex tol, increasing his RR and thus hyperventilation resulting in light headedness?

Having had this experience, I feel I am better equipped to handle such situations should it be presented to me (touch wood).