Last Word on Viewpoint: Physiology and fast marathons

Can We Quantify the Benefits of "Super Spikes" in Track Running?

The recent and rapid developments in track spike innovation have been followed by a wave of record-breaking times and top performances. This has led many to question what role “super spikes” play in improving running performance. To date, the specific contributions of new innovations in footwear, including lightweight, resilient, and compliant midsole foam, altered geometry, and increased longitudinal bending stiffness, to track running performance are unknown. Based on current literature, we speculate about what advantages these features provide. Importantly, the effects of super spikes will vary based on several factors including the event (e.g., 100 m vs. 10,000 m) and the characteristics of the athlete wearing them. Further confounding our understanding of super spikes is the difficulty of testing them. Unlike marathon shoes, testing track spikes comes with a unique challenge of quantifying the metabolic energy demands of middle-distance running events, which are partly anaerobic. Quantifying the exact benefits from super spikes is difficult and we may need to rely on comparison of track performances pre- and post- the introduction of super spikes.

Marathon race performance increases the amount of particulate matter deposited in the respiratory system of runners: an incentive for "clean air marathon runs"

Background

In the last decades, marathon running has become a popular form of physical activity among people around the world. It should be noticed that the main marathon races are performed in large cities, where air quality varies considerably. It is well established that breathing polluted air results in a number of harmful effects to the human body. However, there have been no studies to show the impact of marathon run performance on the amount of the deposition of varied fractions of airborne particulate matter (PM) in the respiratory tract of runners. This is why the present study sought to determine the impact of marathon run performance in the air of varying quality on the deposition of the PM₁, PM_2.5, PM₁₀ in the respiratory tract in humans.

Methods

The PM₁, PM_2.5 and PM₁₀ deposition was determined in an “average runner” (with marathon performance time 4 h: 30 min) and in an “elite marathon runner” (with marathon performance time 2 h: 00 min) at rest, and during a marathon race, based on own measurements of the PM content in the air and the size-resolved DF(d) profile concept.

Results

We have shown that breathing air containing 50 µg m⁻³ PM₁₀ (a borderline value according to the 2006 WHO standard - still valid) at minute ventilation (V_E) equal to 8 L min⁻¹ when at rest, resulted in PM₁₀deposition rate of approximately 9 µg h⁻¹, but a marathon run of an average marathon runner with the V_E = 62 L min⁻¹ increased the deposition rate up to 45 µg h⁻¹. In the elite runner, marathon run with the V_E= 115 L min⁻¹ increased PM₁₀ deposition rate to 83 µg h⁻¹. Interestingly, breathing the air containing 50 µg m⁻³of PM₁₀ at the V_E = 115 L min⁻¹by the elite marathon runner during the race resulted in the same PM₁₀deposition rate as the breathing highly polluted air containing as much as 466 µg m⁻³ of PM₁₀ when at rest. Furthermore, the total PM₁₀ deposition in the respiratory tract during a marathon race in average runners is about 22% greater (203 / 166 = 1.22) than in elite runners. According to our calculations, the concentration of PM₁₀in the air during a marathon race that would allow one not to exceed the PM₁₀ deposition rate of 9 µg h⁻¹should be lower than 10 µg m⁻³ in the case of an average runner, and it should be lower than 5.5 µg m⁻³ in the case of an elite runner.

Conclusions

We conclude that a marathon run drastically increases the rate of deposition of the airborne PM in the respiratory tract of the runners, as a consequence of the huge V_E generated during the race. A decrease of the PM content in the air attenuates this rate. Based on our calculations, we postulate that the PM₁₀ content in the air during a “clean air marathon run”, involving elite marathon runners, should be below 5.5 µg m⁻³.

The Optimal Ambient Conditions for World Record and World Class Performances at the Berlin Marathon

The “Berlin Marathon” is the fastest marathon racecourse in the world and has witnessed 11 world records (WRs; eight in men and three in women). Weather conditions can have an important impact on race time and we therefore examined the influence of environmental conditions (i.e., temperature, sunshine, precipitation, barometric pressure, and cloud cover) on WRs and elite (i.e., winner, top three and top 10 finishers) marathon performances of men and women at the “Berlin Marathon” between 1974 and 2019. Average world record marathon times in men were 2:03:52 ± 0:01:19 h:min:s and 2:25:05 ± 0:08:25 h:min:s in females (p < 0.05). Male competitions were held 44 times (mean winning time: 2:09:48 ± 0:09:15 h:min:s) and female competitions 41 times (mean winning time: 02:30:35 ± 0:19:09 h:min:s; p < 0.05). World record performances were set at mean temperatures of 18.61 ± 2.59°C for men and 13.07 ± 4.01°C for women (p > 0.05). The ideal environmental conditions for world record performances for men were temperatures of 18.61°C (p > 0.05), sunny, mostly dry days, with higher atmospheric pressure and little cloud cover (all p > 0.05). In women, ideal conditions for world records performances were temperatures of 13.07°C (p > 0.05), with low atmospheric pressure (p > 0.05), but significantly more rain (p < 0.05), and with no sunshine (p < 0.05) and cloud cover (p < 0.05). With elite performances, the ideal temperatures were of 17.36 ± 4.33°C for men and 17.93 ± 4.07°C for women (p > 0.05), with little to no rain, and moderate cloud cover and sunshine (p > 0.05). In summary, novel findings are, that environmental conditions in world records performances differ between men and women, with women obtaining world records in bad weather (with rain, cloud cover, and no sunshine) and men in good weather (sunny, mostly dry days, with little cloud cover). Larger sample sizes are needed to examine sex differences and environmental conditions on world record marathon performances.

Physiological and Race Pace Characteristics of Medium and Low-Level Athens Marathon Runners

This study examined physiological and race pace characteristics of medium- (finish time < 240 min) and low-level (finish time > 240 min) recreational runners who participated in a challenging marathon route with rolling hills, the Athens Authentic Marathon. Fifteen athletes (age: 42 ± 7 years) performed an incremental test, three to nine days before the 2018 Athens Marathon, to determine maximal oxygen uptake (VO2 max), maximal aerobic velocity (MAV), energy cost of running (ECr) and lactate threshold velocity (vLTh), and were analyzed for their pacing during the race. Moderate- (n = 8) compared with low-level (n = 7) runners had higher (p < 0.05) VO2 max (55.6 ± 3.6 vs. 48.9 ± 4.8 mL·kg-1·min-1), MAV (16.5 ± 0.7 vs. 14.4 ± 1.2 km·h-1) and vLTh (11.6 ± 0.8 vs. 9.2 ± 0.7 km·h-1) and lower ECr at 10 km/h (1.137 ± 0.096 vs. 1.232 ± 0.068 kcal·kg-1·km-1). Medium-level runners ran the marathon at a higher percentage of vLTh (105.1 ± 4.7 vs. 93.8 ± 6.2%) and VO2 max (79.7 ± 7.7 vs. 68.8 ± 5.7%). Low-level runners ran at a lower percentage (p < 0.05) of their vLTh in the 21.1-30 km (total ascent/decent: 122 m/5 m) and the 30-42.195 km (total ascent/decent: 32 m/155 m) splits. Moderate-level runners are less affected in their pacing than low-level runners during a marathon route with rolling hills. This could be due to superior physiological characteristics such as VO2 max, ECr, vLTh and fractional utilization of VO2 max. A marathon race pace strategy should be selected individually according to each athlete's level.