Age and Intensity

I just got an email from someone on one of my favorite topics - aging and training. I've grown old thinking about this topic. Here's his question and my reply.

Q: I was having a conversation with a friend the other day about 45+ masters racing. We are both a decade or so away from 45+, so I'm not exactly sure why it became a topic of conversation. Like any good discussion/debate there were a series of point and counterpoints. I'll spare you the entire dialogue. Fundamentally, we were discussing the pros and cons to road racing in your 40s-50s. My unsubstantiated opinion is that aerobic exercise, including intensity just above or below LT, is probably good for overall strength and health; but I have my doubts about the benefits of anaerobic efforts for riders approaching their 50s. My unsubstantiated conclusion was that crits and road races probably do more harm than good, and middle aged or aged riders might get more benefit from steady state events.

A: Great topic. But I disagree strongly with you. I'm a big proponent of maintaining or even increasing the percentage of high intensity one does as he/she ages. Otherwise we begin to lose muscle mass. I see many older athletes who have done as you suggest and I've seen them wither over the years. The ones who raced and trained at high intensity stayed much more muscular and lean. At age 65 I do intervals and hill repeats several times a week.

Aging and Performance

When I was in college 40-some years ago the track coach had all the runners do the same workout every day. It was a killer. What I would today call “anaerobic endurance” training. After we warmed up he would blow his whistle and all of us would report to the start line on the cinder track. We knew what was next. He’d blow his whistle again and we’d take off running 440 yards (1 lap) as fast as we could go. As we crossed the finish line he’d call out our times from his handheld stopwatch.

We’d all stand there with our hands on our knees panting while he told us slow we were and that we needed to get faster. Then, when he felt like it, he’d blow the whistle again and off we’d go on the second interval. This could go on for 6 or 10 or 15 of these. Whatever he felt like having us do that day. There was never any talk about pacing, how long the recoveries would be, or how many we were going to do. When people started throwing up the workout usually ended. So I came to call this Intervals Til You Puke. It was a killer workout and wasn’t any fun. I didn't run again for 11 years after I graduated because of this workout. And we’d do this four or five times a week. The only break would be the day before a track meet, and, of course, on the weekends. Nobody trained on the weekends back then. And this sort of “training” (I use the word loosely) went on for the entire track season.

At age 20 I could bounce back and do this workout day, after day, after day. Now I might be able to occasionally do two of these sessions in a week. One is more likely. I simply couldn't spring back. There’s no question that aging impacts recovery. And, of course, recovery has to do with performance. The faster one recovers the more challenging workouts that can be done in a given period of time. The harder the training is, the greater the resulting performance.

What we find in the real world of sport is that as we get older performance drops. There is a steady decline from one’s mid-30s through the seventh decade of life. Then at about age 70 there is a rapid decline in performance. This is evident when looking at age group bests in marathon running as demonstrated by the accompanying chart. And it appears to happen in a wide range of endurance sports.

Again, there is very little in the way of scientific research to support this, but there was one such study of swimmers that came out of the University of Colorado a few years ago. This research [1] showed exactly what I described above: A steady decline in performance until age 70 when there was a significantly greater decrement.

Why does this happen and what can be done about it? There is very little research on aging athletes. That will change in the next few years, I’m certain, since the Baby Boomers are now becoming seniors in large numbers.

The only studies I can find on the topic of recovery in aging athletes come out of Australia. Both used the same data gathered from nine athletes averaging 24 years of age and nine athletes averaging 45 years [2,3]. They each did three, 30-minute, cycling time trials on three subsequent days. Their performances were measured and they recorded subjective perceptions of muscle soreness, fatigue and recovery before each time trial. Interestingly, there was no difference in performance declines between the younger and older groups over the three-day period. However, the older athletes reported significantly more soreness and fatigue, and lower levels of recovery compared with the younger riders. I suspect that had they gone beyond three days of hard workouts they would have soon found a performance decline in the older athletes before it showed up in the younger ones. And had they used even older athletes they may have seen performance declines within three days. But that is just conjecture on my part.

Again, with limited research on the topic there is not much to go on when trying to determine a cause. A study of aging rats found that protein synthesis in type I muscle set them apart from young rats who recovered much more quickly from consecutive days of endurance exercise [4]. A review of the limited literature on the topic confirmed this conclusion about protein in humans [5].

So what does all of this mean for you as an aging athlete? Should you be eating more protein as you get older? The answer to that question is not certain. I know of only one study that found taking in protein soon after exercise stimulated protein synthesis in aging subjects [6]. It might help.

Most of the research relative to eating protein has to do with moderately active or inactive, older subjects needing to maintain muscle mass rather than recover from highly stressful workouts [7,8,9]. This may have little or nothing to do with an athlete’s need for protein but is more food for thought.

The real key for aging endurance athletes is frequent recovery time. All athletes need down time on a regular basis. Older athletes simply need it more often than their younger counterparts. I’ve found that most of the 50-and-older athletes I’ve coached over the years need two to three days of easy training following a highly stressful workout. A young athlete may do two of these sessions back to back and then require only one or two days to fully recover. But not the older athlete. How great the stress is that triggers this long recovery block is an individual matter. Every athlete should have a good idea of what different types of workouts demand in the way of recovery.

In the same manner, all athletes need extended recovery periods every few weeks during periods of heavy training. Younger athletes can go perhaps three to five weeks before needing to take a break for three to five days. For the 50-plus athlete it is seldom more than two weeks before down time is necessary in order to prevent overtraining. Extending the period of heavy training beyond this or skipping these rest blocks is likely to result in unrelenting fatigue and greatly reduced performance.

References
1. Donato, A.J., K. Tench, D.H. Glueck, D.R. Seals, I. Eskurza, H. Tanaka. Declines in Physiological Functional Capacity with Age: A Longitudinal Study in Peak Swimming Performance. Journal of Applied Physiology, 2003, 94(2):764-769.
2. Fell, J., L. Haseler, P. Gaffney, P. Reaburn, G. Harrison. Performance During Consecutive Days of Laboratory Time-Trials in Young and Veteran Cyclsists. Journal of Sports Medicine and Physical Fitness, 2006, 46(3): 395-402.
3. Fell, J., P. Reaburn, G.J. Harrison. Altered Perception and Report of Fatigue and Recovery in Veteran Athletes. Journal of Sports Medicine and Physical Fitness, 2008, 48(2): 272-277.
4. Spangenburg, E.E., T. Abraha, T.E. Chails, J.S. Pattison, F.W. Booth. Skeletal Muscle IGF-Binding Protein-3 and -5 Expressions Are Age, Muscle and Load Dependent. American Journal of Physiology and Endocrinology, 2003, 284(2): 340-350.
5. Thompson, L.V. Skeletal Muscle Adaptations With Age, Inactivity, and Therapeutic Exercise. Journal of Orthopedics, Sports, and Physical Therapy, 32(2): 44-57.
6. Dorrens, J., M.J. Rennie. Effects of Aging and Human Whole Body and Muscle Protein Turnover. Scandinavian Journal of Medicine and Science in Sports, 2003. 13(1): 26-33.
7. Young, V.R. 1990. Protein and Amino Acid Metabolism With Reference to Aging and the Elderly. Progressive Clinical Biology Research, 1990, 326: 279-300.
8. Parise, G. Yarasheski, K.E. The Utility of Resistance Exercise Training and Amino Acid Supplementation for Reversing Age-Associated Decrements in Muscle Protein Mass and Function. Current opinions in Clinical Nutrition, Metabolism and Care, 2000. 3(6): 489-495.
9. Esmarck, B., J.L. Andersen, S. Olsen, E.A. Richter, M. Mizuno, M. Kjaer. Timing of Post-Exercise Protein Intake Is Important for Muscle Hypertrophy With Resistance Training in Elderly Humans. Journal of Physiology, 2001, 535(Pt 1): 301-311.