Friday, November 7, 2008

Slowing with Age?

We started our current diet 10 months ago in an attempt to regain our health and vitality and lose some of the weight that had crept on over the last few years. We appeared to be developing signs of metabolic syndrome despite our frequent hikes, and it was time for more drastic measures. We love the outdoors and hiking, so it was natural to combine hiking/jogging with the low carb diet we began last January. Initially, we did much the same routes as we’d been doing on our casual hikes for the last two years. We gradually increased the challenge of our outings, trying to find ways to connect different parks, no longer being satisfied with the ~8–11 miles available in most parks. At first, these longer outings seemed long and took a lot of time: 12, 15, 18 miles. I experienced my first nausea during and after an 18-mile run/hike (with a couple of thousand feet of elevation change). That just made me mad and I wanted to tackle it again, this time with a bit of food to see if the nausea could be prevented (it worked). Then on a whim, we did our first 50K (Headlands 50K—cool but very hilly), and got seriously addicted to ultra events and pursuit of improved fitness. The first was slow (8.5 hr), which again made me mad and determined to do better. The second (Stevens Creek 50K—see Mark Tanaka’s race report) was worse for me at least (9.5 hr, but very hot and hilly, very low finish rate), though David tolerated the heat much better and did quite well (~7 hr). The third was getting better, but still unacceptably slow (Skyline-to-the-Sea: 7 hr, and net downhill. See Scott Dunlap’s race report). Our fourth ultra was the Firetrails 50-miler which took 12 hours (at least, not a slower pace than previous races; see Jean Pommier’s race report ). Undeterred, a couple of weeks later I ran 49 miles (again in 12 hours at the SF One Day—another painful story).

So why so slow? I’m 52 years old, and seem to have lost much of whatever speed I ever had (a middle of the pack sprinter in high school and college). I was on track for a 3:20 marathon before a calf injury slowed me down—PR of 3:27), now 25 years ago. Just how slow must I be now? Is it possible for a person to regain the health and vigor they had when they were younger? This is the grand experiment, and may fail badly, but that’s the question. Can I get back what I once had? Can I get better? Do I have to be resigned to being old and slow? Can I improve my health while I do it?

So it seems it’s time for some more serious training. We’ve started doing small interval workouts on the track (a few 200s, 400s and 800s) and some tempo runs, just to try to jog the memory of those quiescent fast twitch muscles (no pun intended). I was dismayed to realize that I’ve lost all sprint speed, and running up on my toes feels like I’m going to spazz out and fall on my face. Just doing 400s at an 8-minute-mile pace seems fast at this point. I’m hoping that will change, but how to improve?

Recently, I came across a link to a blog I haven’t discovered before, with an interview with Dr. Maffetone about training for endurance events that was quite interesting. He’s the inventor of the 180 rule (basically subtract your age from 180 to calculate your maximum aerobic heart rate [HR]). According to this method, you train at a level that achieves the desired HR, and you naturally speed up even though you maintain this level of effort, as you train your body to use fat as fuel. In the interview, he describes how he discovered this method basically by measuring respiratory quotients to determine at what HR fat burning occurred as opposed to carbohydrate burning. According to Dr. Maffetone, anaerobic training can be implemented after base aerobic training, in interval workouts or races, then followed by more base training.

I was intrigued and read some of the other advice on his website (sign up for a free membership). His nutrition advice really surprised me as well—another low carber of sorts! He advocates cutting out all refined carbohydrates, much the same advice of the cardiologist Dr. William Davis who is working hard with his patients to prevent and reverse their atherosclerotic disease.

It’s possible that we’ve already achieved a good grounding in aerobic (fat burning) ability, and that now would be a good time to work on speed. Maybe a good test would be to run a regular road marathon to at least get a good baseline number on my starting point. We’ll have to see how it goes…


Julianne said...

I think it's awesome that you're still running! It's quite inspirational, really.

Drs. Cynthia and David said...

Thanks Julianne. I just don't want to act my age!

I want to hear more about your speed workouts and such.


Evan said...

I think everyone slows with age but I do have a couple of 50+ year old freinds that are still throwing down sub 36 minute 10ks. They do one hard speed workout a week and then do nothing but recovery runs the other days. Speed work in so important even when training for ultras.

Drs. Cynthia and David said...

Thanks for your comment Evan. Why exactly do we slow down though? It is cardiovascular limitation or something else?

It would be nice to be able to run a 36 min 10k! It's good to hear that some people at my age can still manage that. I doubt I was ever capable of that though!

I do think the speed work is helping, but I am still having significant stress responses from either long mileage or harder efforts. I'll post a blog about that at some point to describe what we've observed.


olga said...

The facts do say we should slow, and most of us do...but then we have my training partner and friend Mike Bushwhacker Burke, who is 58, and kicks booty in any distance above a marathon, on trails, locally and nationwide (11th place at Hardrock 100 this summer). I am not even talking about 40+ "youngsters", who kill ultras all over the country!
At least I tell myself there is hope:)

Drs. Cynthia and David said...

Thanks Olga. I'm not giving up yet. In fact, we just had a 30 min improvement in a 50K trail PR, and I was so thrilled (and sore for days!)!

It think the slowing may be related to heart rate limitations, but I'm not even sure if they are necessary either. I'm still so far from whatever speed I used to have that there is still lots of room for improvement. On the other hand, David is doing quite well even though he is training with slow me most of the time.

Thanks for visiting.