I am involved in a research project at UVM developing interventions to enhance stride length (and therefore speed!) in older runners. These interventions are jumping and skipping plyometric-form drills I’ve previously blogged about. Borrowing from what John Babbington prescribed for his Wellesley cross country team and also discussed by Peter Reaburn in The Masters Athlete, I have been consistently doing these for over 20 years. I firmly believe I’ve benefitted from this regimen.
The premise of plyometrics rests upon generating maximum force in the shortest time (Reaburn, 2009.) To be clear, the drills I use and prescribe for older runners are not as intense as the ones you’ll see demonstrated online by college or younger athletes. But they do generate force quickly! Through this research, I’m looking to expand this practice beyond myself and those I’ve coached.
As part of a proposed research paper, I’ve described how the expected decline in endurance running speed accelerates after age 50. This took me right to the World Masters Athletics (WMA) adopted age grade (AG) tables, which most of us are probably familiar with. At root, these tables are derived from best-ever times reported by age and gender for various distances. The computed age grade percentage (AG%) is the ratio of a competitor’s performance to the best-ever time. There is a statistical adjustment to keep outliers from distorting the tables.
| Age (Men) | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
| AG%. 5K in 21:00 | 62.0 | 63.2 | 65.3 | 67.7 | 70.2 | 73.0 | 76.0 | 79.3 | 83.2 | 89.3 | 98.7 |
| 5K time @ 80% AG: | 16:16 | 16:35 | 17:09 | 17:46 | 18:26 | 19:10 | 19:57 | 20:48 | 21:50 | 23:26 | 25:55 |
| 5-yr % decline | .1% | 1.8% | 3.3% | 3.5% | 3.9% | 4.0% | 4.1% | 4.3% | 5.0% | 7.4% | 10.5% |
| % decline/ yr | .02% | .4% | .7% | .7% | .8% | .8% | .8% | .9% | 1.0% | 1.5% | 2.1% |
| Cumulative % decline: | .1% | 1.9% | 5.5% | 9.2% | 13.1 | 17.6 | 22.4 | 27.6 | 33.9 | 43.9 | 59.0% |
| Age (Women) | 30 | 35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
| AG%. 5K in 23:00 | 64.2 | 64.6 | 65.9 | 68.3 | 71.8 | 75.9 | 80.6 | 85.8 | 91.8 | 98.6 | 106.7 |
| 5K time @ 80% AG | 18:27 | 18:35 | 18:57 | 19:38 | 20:38 | 21:50 | 23:10 | 24:40 | 26:24 | 28:21 | 30:41 |
| 5-yr % decline | ~0 | .7% | 2.0% | 3.6% | 5.1% | 5.8% | 6.1% | 6.5% | 7.0% | 7.4% | 8.3% |
| %decline/yr | ~0 | .1% | .4% | .7% | 1.0% | 1.2% | 1.2% | 1.3% | 1.4% | 1.5% | 1.7% |
| Cumulative % decline | .7% | 2.7% | 6.4% | 11.9 | 18.3 | 25.6 | 33.7 | 43.1 | 53.7 | 66.4% |
Two ways to use the AG tables are: (1) determine an achievable time for a given distance and note how the age grade percentage changes with age; (2) choose an AG% for an open runner and see how race time increases with age. The above tables employ both methods, using a 21:00 5K for men and 23:00 for women and an 80% age grade. Selecting these times and % was arbitrary, though an 80-90% AG performance is considered national caliber. This is a broad range, with 80% on the lower end of the spectrum, though still a very strong performance achieved by less than 10% of the field in most races, and 89% bordering on world class. You may have noticed more races reporting results both by net finish time and AG%.
The above tables illustrate that an 80% age grade percentage is maintained by achieving progressively slower times. For men, an open time of 16:16 converts to 18:26 by age 50 (a cumulative 13.1% decline) and 21:50 by age 70 (a cumulative 33.9% decline). For women, an open 80% AG% time of 18:27 declines to 20:38 (an 11.9% cumulative decline) by age 50 and then to 26:24 minutes by age 70 (a 43.1% cumulative decline). The tables indicate women decline at a slower rate than men until age 45 and then more rapidly beyond age 50.
So, this is what is expected of us as we age. It’s pretty bleak, really! By 60, men are expected to have slowed 22%, and by 70 34%. Not something to look forward to!! The good news is these are averages and some individuals are able to “beat” these rates of decline and show increased AG%s as they age. That’s what my research study is about — introducing plyometric interventions aimed at maintaining or even increasing speed in runners over 50, and thus the AG%!
Stay tuned, and if you are interested in being in the study, please reach out.