Hi Anat:
I had to give up impact activities for about 7 months while dealing with a very stubborn case of plantar fasciitis(PF) in my left foot. It started out mild, but eventually got so bad that I could barely walk.
Before the PF stopped me, I used to do almost exclusively step and running for my cardio. I thought I would go nuts when I had to stop. But there is good news! The injury ended up bringing some new activities into my fitness life that I now love. I started going to the gym and taking indoor cycling (spinning) classes. These are usually 45-minutes long and feature lots of interval work plus provide some resistance training for your legs. I bought some good padded shorts and, later on, some cycling shoes. (Because of my PF, my feet are sensitive to the pedal pressure. Cycling shoes are very stiff and provide excellent protection.)
I also started swimming and pool-running once or twice a week at my local community rec center. I thought I would be bored by the water activities, but I ended up really enjoying them. I went in the morning and swam in the lap lanes and watched my 7-year old son and lots of other kids taking swim lessons. It was very entertaining.
I also was able to do the elliptical trainer at the gym. This simulates running, without the impact. I found that it still sometimes aggravated my PF, so I had to limit the length of my elliptical sessions. But it provided excellent crosstraining.
You never realize how much you depend on strong, healthy pain-free feet until you have a foot that is injured. I hope that you will follow your doctor's advice.
Following is a long aside, but I've learned the hard way, so I'll share. If you have PF, it's really important to ice religiously, stretch your foot before you get out of bed, address the biomechanical issues that caused the PF (this usually means getting prescription orthotics, but sometimes over-the-counter ones will suffice.) Also, wear good shoes with good arch support. If you're doing everything right (as I was) and it's still not improving, it could be that you've developed a lot of scar tissue. Find a doctor, physical therapist or chiropractor that can do ultrasound and cross-fascia massage. And do these treatments 3 times per week. This will help immeasurably and fast! Don't be freaked out if your dr tells you that you have a heel spur. Those are not a big deal and they can be reabsorbed. The cause of the pain is not the spur, it is the inflamed fascia. Treat the inflammation, get rid of the cause, get rid of the scar tissue and go forward.
Whoo. I'm tired from typing. I'm also afraid that I'm beginning to develop a foot fetish or something ... never thought I'd get so passionate about foot issues.
