This topic was addressed by the authors of a scientific review published in the January issue of the Journal of Aging and Physical Activity. In a paper entitled "Why Are Masters Sprinters Slower Than Their Younger Counterparts? Physiological, Biomechanical, and Motor Control Related Implications for Training Program Design" analysed dozens of existing scientific studies on the impact of ageing on athlete performance and attempted to answer the following two questions:
- Why do middle-aged and older sprinters become slower than their younger counterparts?
- How can we use this knowledge to slow down the ageing process and increase the performance of masters athletes?
Why are master sprinters slower?
The studies cited in the review allow the conclusion to be drawn that as the body ages, all of its dynamic motor characteristics that are important for running speed gradually decline. The athletes studied had a shorter stride, a smaller range of motion at the hip joint, a longer ground contact time and a shorter time in the flight phase. The only parameter that does not decrease until around the age of eighty is step cadence.
Biomechanical abilities also decline. Middle-aged sprinters, compared to younger athletes, had significantly lower knee and foot extensor muscle volume, as well as worse performance in the countermovement jump and lower 1 RM in the half squat (1 Repetition Maximum, which is the maximum weight we are able to lift once). This shows that there is a decrease in muscle strength and power. In older athletes, it has also been noted that there is a lower proportion of type II and IIA fibres with no change in the proportion of type I fibres. These are the reasons why there is a decrease in stride length and an increase in ground contact time.
The scientific studies reviewed in this review show that, as we age, muscle strength and coordination decline earlier. Muscle mass reduction occurs much later.
The earliest functional losses of the muscular system are due to the gradual degradation of neural connections. This includes primarily loss of motor neurons and degeneration of nerve axons causing abnormalities in the transmission of nerve impulses.
Why does this happen? Throughout life, motor neurons and muscle fibres are repeatedly disconnected and reconnected. Not all such subsequent connections are perfect, sometimes errors occur. Over time, the build-up of these errors causes some of the motor neuron endings to stop doing their job.
Once disconnected from a motor neuron, the muscle fibres cease to participate in movement and become atrophied, unless they are previously successful in connecting to another neuron. In the latter case, the muscle fibre can still function, but the motor neuron has more muscle fibres to "handle" than before. Therefore, the functions of these neurons become less and less efficient and this causes a decrease in muscle strength and power, reduced coordination and an increased risk of injury.
How to train to stop ageing?
Since type II and IIA fibres atrophy most quickly as we age, the authors of the scientific studies analysed recommend that exercises should target the activation of these particular muscles. Maintaining their size and strength should be a priority from middle age onwards.
The following set of exercises performed 2-3 times a week has been suggested:
4 weeks hypertrophic phase (increase muscle fibre volume)
- 3-4 series of 8-12 repetitions 50-70% 1RM
Several weeks of maximum strength phase + explosive strength + plyometric exercises
- maximum strength: 2-4 series of 4-6 repetitions 70-85% 1RM
- explosive strength training (maximum power): 2-3 series of 3-10 repetitions 35-60% 1RM)
- plyometric exercises: 2-3 series of 3-10 repetitions
These training elements were performed alternately to aid recovery.
The strength training focused on leg extensors and hamstrings, i.e. leg press, half squat, Romanian deadlift with complementary exercises (bench press, push press). The plyometric part included jumps up and long jumps.
Using appropriate sets of exercises achieved:
- 21% increase in knee joint extensor strength,
- 40% increase in knee joint flexor strength
- 27% increase in 1RM in the squat
- 10% improvement in power in the countermovement jump
A greater effect on type II and IIA fibres has also been reported.
Existing research suggests that both strength and plyometric exercises should be an important part of sprinters' training and speed training. They may even reverse some of the effects of ageing and the effects of a sedentary lifestyle.
Rules of exercise prescription
It's also important to note that with older athletes, it's important to carefully select exercises to get the most effectiveness out of them. Conventional isotonic and especially concentric strength exercises (i.e. causing shortening of muscle fibres) require a lot of energy and do not optimally stimulate tissue remodelling, they only generate more tension in a very short time. In contrast, isometric (which does not cause a change in the length of the muscle) or eccentric exercises (which cause tension during the lengthening of the muscle), require less energy and at the same time generate the appropriate tension and a remodelling stimulus for the muscle tissue.
A more targeted and effective prescription of exercises can increase their effectiveness in older athletes. For example, several studies show that performing repetitions of strength exercises to refusal of movement does not increase training effects in healthy older men.
What effect does this have on running fast? High muscle stiffness of hamstrings is important for speed. It has been proven that isometric or eccentric exercises are far more effective for this muscle group. So to minimise the risk of injury the Nordic curl exercise is usually recommended.
It is also worth using unconventional load schemes, for example series including clusters. It has been proven that this is more effective for improving strength and power in middle-aged and older athletes. Clusters are dividing the series with additional short breaks of about 30 seconds.
Some exercises may also be more beneficial for older athletes, although they don't benefit younger athletes very much. One example is exercises involving balancing on one leg. They improve muscle coordination, which starts to be lacking from middle age onwards.
Here you will read the second part of this article, in which I will describe the other issues affected by masters athletes and the review authors' suggested ways to support training.
Sources:
- Why Are Masters Sprinters Slower Than Their Younger Counterparts? Physiological, Biomechanical, and Motor Control Related Implications for Training Program Design, Craig Pickering, Dylan Hicks, John Kiely
- Korhonen, M.T., Mero, A.A., Alen, M., Sipilä, S., Häkkinen, K., Liikavainio, T., Suominen, H. (2009). Biomechanical and skeletal muscle determinants of maximum running speed with aging. Medicine & Science in Sports & Exercise, 41(4), 844–856, pubmed
- Goodpaster, B.H., Park, S.W., Harris, T.B., Kritchevsky, S.B., Nevitt, M., Schwartz, A.V., Newman, A.B. (2006). The loss of skeletal muscle strength, mass, and quality in older adults: The health, aging and body composition study. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 61(10)
- Cristea, A., Korhonen, M.T., Häkkinen, K., Mero, A., Alén, M., Sipilä, S., Larsson, L. (2008). Effects of combined strength and sprint training on regulation of muscle contraction at the whole-muscle and single-fibre levels in elite master sprinters. Acta Physiologica, 193(3), 275–289. PubMed