I say go for it. Just train well and be prepared to hit the 'wall'.
Read as much as you can about different training programs and tips to
get you through. Try different things on your long runs - clothes,
gels, etc...
I'm 26 years old and have ran two marathons. My first was Cleveland
in 2005. Afterwards I realized I wasn't prepared. I didn't know
about the 'wall' and I didn't realize how hard those last 6 miles were
going to be. I didn't use any gels. I hadn't trained in the clothes
I planned on wearing. I had set a goal - something I would NOT
recommend doing. But I had trained well and was only sore one day,
which helped me forget how painful those miles had been at the
end.
After that I decided I would only do a marathon if it was someplace
fun. Kind of silly, but I made the deal with myself that if I was
going to put in the time and effort to train, I was going to pick one
I really wanted to do. My second was the Nike Womens Marathon in San
Francisco last year. I LOVED it. I got there 4 days early, saw the
city, did the pre-race stuff, met up with friends and family. The
race was fantastic. It was perfect running weather. There were
thousands of people (mostly other women). It was just an awesome,
empowering experience. And to top it off I was greeted at the finish
line by the firemen in tuxedo's handing out the finisher 'medal' - a
necklace from Tiffanys in the perfect little green box.
This time I trained differently. I ran in all sorts of 'outfits' to
see what was most comfortable. I had the hardest time with socks of
all things - I had gotten blisters on my toes early in my training and
then they just kept coming back. I trained using different gels until
I found one that I liked and didn't upset my stomach. I studied the
course map and elevation. I made myself a training schedule - longer
than the ones I was finding online and in books - because I know my
legs needed a little extra time to recover from long runs. I did
hills or speedwork once a week. I ran a half marathon as part of my
training to guage where I was training-wise. I didn't stress when I
had to take a couple of weeks off for knee pain - instead I adjusted
my training schedule slightly and started back into it. But most
importantly I didn't set a time goal. I just went out and ran for
fun, no stress. And I actually ran faster.
I guess this is just my way of saying you should do it. It's a great
experience and it is so rewarding.
And don't worry about age or pace - my 51 year old aunt just ran the
Maui Oceanfront Marathon in just under 7 hours.
Erin