Endurance Exercise - Does it makes us older, or younger?

These two articles seem to contradict one-another.

The first, by Mark Sisson, was published on Slowtwitch.com. It suggests that aerobic endurance exercise (running, cycling, triathlon) accelerates aging, as opposed to intense anaerobic exercise (weight lifting, sprinting), which allegedly slows down the aging process.

Training Is No Guarantee of Health

The second appeared on the front page of today's Washington Post.

Exercise Slows Down Aging

It reports on a study of 2,400 British twins, the results of which suggest that exercise slows down the aging process, and that the more you exercise the younger your cells appear.

I'm inclined to believe the King's College study over Sisson's half-baked theories, but that could just be me wanting to justify my lifestyle.

What do you think?

P.S. -- I won't get into Sisson's provactive statements regarding testosterone therapy, or its implications for amateur age-group athletes.

Addendum: I recently ran across a more comprehensive article on exercise and aging, courtesy of Havard Men's Health Watch.

Exercise and aging: Can you walk away from Father Time?

The bottom line is that endurance exercise, resistance exercise, flexibility training, and balance exercises all play a roll in staving off many of the effects of aging.

Remember: 40 is the new 30, and, as Mark Twain put it:

Age is an issue of mind over matter. If you don't mind, it doesn't matter. ~Mark Twain