Lifelong physical activity is an important determinant of health and wellbeing, and it becomes increasingly important as we age. With the passing years, increased levels of muscle mass—and the maintenance of that mass—are associated with better preservation of function and lower rates of all-cause mortality in the elderly. As we’ve become more aware of this relationship between activity and health as we age, more older adults are turning to organized sports to motivate them to maintain their fitness. One increasingly popular area is Masters Athletics.
Like its mainstream counterpart, the open age group championships, Masters Athletics has a competitive arm, which includes World and European Championships. Competing in these championships drives the motivation of many masters athletes to improve and progress. In this article, I take a subset of masters athletes—masters sprinters—and discuss what we know about their performance. And given what we know, how to use the information to support the sprint performance of these athletes.
Why Are Masters Sprinters Slower?
The men’s 100m world record, held by Usain Bolt, is 9.58 seconds. Bolt was not quite 23 years old when he ran that time—which, in terms of human lifespan, is relatively young. And yet, what the general pattern of performance tells us is that, after our twenties, we tend to get progressively slower with age.
- The M35 100m world record is 9.87 seconds, run by Justin Gatlin (who has a PB of 9.74, achieved at age 33).
- The M40 record, 9.93 seconds, is held by Kim Collins (which, surprisingly, is his personal best).
- Willie Gault holds the records for M45, M50, and M55 (10.72, 10.88, and 11.30, respectively; Gault’s absolute PB is 10.10, which he ran age 21 before playing in the NFL).
This trend holds in the longer sprints and in women’s sprint events.
- In the 200m, the absolute WR is 19.19, the M35 record is 20.11 (Linford Christie), the M50 record is 22.44 (Willie Gault), and the M70 record is 25.75 (Charles Allie).
- In the women’s 100m, the absolute WR is 10.49, compared to a W35 record of 10.74 held by Merlene Ottey (which, like Collins, is her personal best), a W45 record of 11.34 (Ottey again), and a W55 record of 12.80 seconds (Nicole Alexis).
The clear trend here is that performance declines with age. Although some can peak in their mid-30s, most do so earlier. And, after age 40, all are slower. To develop key training strategies, we need to understand why.
Several studies have explored this in detail from a sprint mechanics standpoint. In 1993, the Journal of Applied Biomechanics published Nancy Hamilton’s paper, where she reported data on 162 elite master’s runners. The results demonstrated that, unsurprisingly, running velocity decreased the older the athletes got, from 8.93 m/s in the 30-40 age group to 4.91 m/s in the over-90s group of male sprinters. As sprint velocity is essentially a product of stride length and stride frequency, Hamilton then explored differences in these two variables with increasing age. Again, stride length (in this case, defined as one complete cycle, meaning right foot to left foot to right foot again) decreased substantially with age, from an average of 4.35m in the 30-40 year age group to 2.84m in the over-90s.
On average, there was a decline of 20-30cm of stride length per decade. This occurred with a concurrent increase in support time (time on the ground) with age, and a decrease in time spent in the air. In the latter case, the time changed from 0.12s in the 30-40 age group to 0.085s in the over-90s (as a brief aside, typically elite sprinters spend much more time in the air than they do on the ground; 0.085s is about the amount of time that world-class male sprinters spend on the ground per stride).
A similar study generally supported Hamilton’s findings. In this 2003 paper, a group of Finnish researchers collected sprint mechanics data from the 2000 European Veterans Athletics Championships with a total of 37 males and 33 females taking part, including at least one of the top four finishers in each age category. Generally, the younger athletes achieved their maximum velocity significantly earlier in the race than the athletes in the older age bands. The 40- to 49-year-old men achieved maximum velocity at around 45m compared to 25m for those in the 80- to 89-year age group. Stride rate (comprised of airtime and support phase) decreased with age, as did stride length, but these changes in stride rate were only significant during acceleration. Again, the time spent on the ground per stride increased with age, while time in the air decreased. As a result, the authors concluded that masters 100m sprinters get slower primarily due to a decrease in stride length and an increase in ground contact time with both males and females.
A more recent study, this time from 2019, provides some further insights into how sprint mechanics change in masters compared to younger sprinters. In this paper, the researchers reported that, as sprinters age, their frontside hip mechanics alter; essentially, they’re unable to get their knee as high as their younger counterparts. A key question here—which the paper does not answer—is whether this is due to a reduction in functional range of motion or a reduced capacity to produce the required levels of strength to achieve a high hip angle.
As a quick digression, let’s discuss optimal sprint mechanics. This will be a vast oversimplification, and for a more in-depth discussion, I recommend Mann’s The Mechanics of Sprinting & Hurdling. In general, to run quickly, athletes have to optimize their stride length and stride frequency to best suit their unique makeup. Elite male sprinters generally have a stride frequency of just under 5 Hz (5 steps per second)—typically somewhere in the region of 4.8 Hz. Their stride lengths (right foot to left foot) are usually about 2.5 m at maximum velocity (for women, this is ~2.25 m). Stride length and stride frequency are the key components of maximum velocity. Still, they both have a multitude of constituent factors, as identified in these classic diagrams by Hunter and colleagues (which they adapted from Hay):
There’s also a negative interaction between stride length and stride frequency, such that as one goes up, the other goes down, and vice versa. For example, my stride length at maximum velocity was around 2.25 m—considerably shorter than the 2.54 m average of elite sprinters, and likely the reason why I never became a true elite sprinter. However, my stride frequency was much higher than the average elite sprinter at about 5.3 Hz.
To maximize their stride length and frequency, elite sprinters aim to spend as short amount of time on the ground as possible, typically getting down to around 0.085s per step. This is a huge challenge for sprinters. To maximize their stride length, they need to produce the required amount of force to propel them forward at speed and do so over a very short time period. The shorter amount of time the sprinter spends on the ground, the longer they can relatively stay in the air, meaning their legs can move over a greater range of motion, and they can cover more ground. While in the air, elite sprinters achieve a greater hip flexion angle (they get their knee higher) in front of the body, which again increases their stride’s range of motion, increasing stride length. The increased range of motion in front of the body also increases the range through which the foot can be accelerated toward the ground, increasing the speed it possesses upon ground contact. This reduces the amount of braking force that needs to be overcome, decreasing the amount of time that needs to be spent on the ground.Older elite masters sprinters have shorter stride length due to increased ground contact time and decreased hip flexion angle, says @craig100m. Click To Tweet
In summary, if we compare the above biomechanical profiles of elite sprinters and elite masters sprinters, we see that the older athletes have a shorter stride length. This is due to their increased ground contact time and decreased hip flexion angle, and both of these may be related.
Why Do Masters Athletes’ Sprint Mechanics Change?
Having established that an increase in ground contact time and a decrease in hip flexion angle likely underpin the loss in stride length in masters athletes, the next step is to ask, What causes this? A second Finnish study, from 2009, provides some valuable insight here.
For this study, the authors recruited male sprinters who were young adults (17-33 years old) and older elite masters (40-82 years old), subjecting them to a battery of tests. The authors replicated the findings of the earlier studies. The older sprinters had a reduction in stride length with a concurrent increase in contact time and a decrease in air time. The authors then explored why. First, the older athletes had lower ground reaction forces; they were unable to match the force outputs of their younger counterparts. Apparently, this was related to the muscular properties of the masters sprinters, who had reduced knee extensor and plantar flexor muscle thickness. This loss of muscle thickness was primarily driven by an age-related decline in type-II muscle fiber, meaning that masters sprinters have fewer fast-twitch muscle fibers than the younger adult sprinters. Importantly, there were no differences in muscle fascicle length—something related to sprint ability—between younger and older athletes.
Building on this, the authors also explored differences in strength between the age groups. Perhaps unsurprisingly, the older athletes demonstrated an age-related decline in half squat 1RM strength (dynamic strength), leg extension (isometric strength), power (vertical jump height), and rate of force development. Further analysis showed that, when age was removed from an explanatory model, muscle thickness and vertical jump height were the two factors that best explained the loss of speed.
To summarize, we can clearly see that:
- Masters athletes are slower than younger athletes, primarily due to reductions in their stride length.
- The loss of stride length is primarily due to both an increase in ground contact time and a decrease in ground reaction forces, with the two likely related; an overall loss of strength and power with age means that athletes have to spend longer on the ground to produce a set threshold of force.
- Masters athletes have reduced ground reaction force because they possess lower levels of strength and power than their younger counterparts.
- These lower levels of strength and power are likely due to a loss of type-II muscle fiber due to aging.
What Does This Mean for Training Program Design?
The age-associated loss of type-II muscle fiber appears to be the main driver of loss of speed in masters sprinters. This suggests that, alongside typical sprint training best practice, there should be an emphasis on increasing (or, more realistically, attenuating the age-associated reduction in) type-II muscle fiber size and proportion. To achieve this, we should increase the emphasis on resistance training for many reasons.Stimulating fast-twitch muscle fiber with resistance training may be a crucial training component for masters sprinters, says @craig100m. Click To Tweet
First, resistance training tends to lead to skeletal muscle hypertrophy, and muscle size is generally proportional to muscle strength (although this is still debated). Higher load resistance training is also associated with greater stimulation of fast-twitch muscle fibers and motor units, which increases both the relative size of type-II muscle fibers as well as the muscle’s strength and power characteristics. Resistance training for masters athletes is, therefore, likely to be a crucial component of their training programs.
At this point, we can suggest:
- Training for masters sprinters should primarily aim to offset the reduction in type-II muscle fibers seen with aging.
- As masters sprinters already likely use relatively high volumes of sprinting (one method of maintaining type-II fibers), using high-load strength training, where safe, should assist in maintaining (or minimizing the reduction of) type-II fibers.
- As losses in knee extensor (quadriceps) and plantar flexor (calves) strength are associated with reduced sprint speed, perhaps we should especially target these muscle groups.
- Ballistic and plyometric exercises may help limit the age-associated loss in rate of force development that might be associated with masters sprinters’ loss of speed.
Additional Programming Considerations
As any aging current or former athlete like myself will tell you, it seems to take longer to recover from the big sessions as we age. A 2016 review published in the Journal of Aging and Physical Activity suggested this relationship is potentially a bit more nuanced; as we age, we tend to be less active overall. As a result, we’re less fit and need longer to recover. The key finding from the paper was that there are no apparent differences in recovery between younger and masters athletes from a physical perspective, but that masters athletes may perceive they take longer to recover following exercise. As a result, they tend to reduce their training intensities and volumes to a greater extent than their younger counterparts.
As a result, masters athletes should ensure they optimize their recovery through a variety of means. If they maintain their fitness through maintaining training volume and intensity, it appears they don’t have an increased recovery burden generally. But, as explained below, this is potentially nuanced.
As mentioned earlier, a key strategic pillar of their training should be developing or maintaining type-II muscle fibers, which in turn increases hypertrophy and muscle strength. As we age, we become subject to age-related anabolic resistance, when the muscles of older individuals cannot match the muscle protein synthesis rates of younger athletes. This means that, following exercise that causes muscle damage, there is potentially a longer period of recovery required, something we need to be wary of.Masters athletes should consume 3-4 doses of ~35g of leucine-rich protein per day, with one dose coming directly after exercise, says @craig100m. Click To Tweet
Also, while ~20g of protein can maximally stimulate muscle protein synthesis in younger athletes, older athletes may need a higher dose—closer to 35g of protein—to elicit the same effects. This, in turn, may reduce the age-related anabolic resistance that’s generally present in masters athletes. As a result, a review article from leading researchers in this field suggests that masters athletes should consume 3-4 doses of ~35g of leucine-rich protein per day, with one of the doses coming directly after exercise.Masters athletes should consider both HMB and creatine supplementation to maintain or enhance their muscle mass and strength, says @craig100m. Click To Tweet
Alongside the increased protein intake, masters athletes should consider both β-hydroxy β-methylbutyrate (HMB) and creatine supplementation to maintain (or hopefully even enhance) their muscle mass and strength. HMB is an interesting supplement that was in vogue about ten years ago. When protein intake is adequate, there might not be any additional benefit from HMB supplementation, but the International Society of Sports Nutrition’s position stand suggests it might be useful. There are also several studies on the use of HMB in the elderly. However, most of these involve much older individuals (70 years plus) or sedentary people, so it’s not clear how their results would relate to masters sprint athletes. If athletes do decide to consume HMB, around 3g per day seems optimal. Creatine is another potentially worthwhile supplement, but again the research is typically in untrained and clinical populations.Masters sprinters should use eccentric loading exercises to reduce injury risk in the hamstrings & calves, says @craig100m. Click To Tweet
Finally, research tends to suggest that older athletes are more likely to suffer from a range of muscle and tendon injuries. For example, a recent review on risk factors for hamstring injury suggested that older age was a significant risk factor for a hamstring injury, as was having suffered a previous hamstring injury. As masters athletes are likely to have been training and competing for much longer, they are more likely to have experienced previous hamstring injuries, doubly increasing their risk. Research also suggests that masters athletes have an increased risk of Achilles tendinopathy. As a result, masters athletes should be proactive in their injury risk-reduction training, using eccentric loading exercises to enhance the damage resistance of these structures.
Developing Training for Masters Sprinters
Based on what I’ve written above, I believe it’s clear that masters sprinters should follow typical best sprint training practices. However, we need to increase emphasis on building or, most likely, maintaining the relative proportion of type-II muscle fibers the athlete has, primarily through high-load resistance training and plyometric exercises.
Alongside this, injury reduction exercises for the hamstring and calf muscles are important to mitigate any age-associated increase in injury risk, while also understanding that highly damaging exercise, such as eccentric loading, may increase their recovery times even further. Finally, from a nutritional standpoint, masters athletes should aim to consume about 35g of protein multiple (3-4 times) per day, including after exercise, and may wish to supplement with HMB and creatine. By following these simple guidelines, we should be able to maintain the current performance levels of masters athletes for longer, enhancing their relative performance well into the future.
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