RESEARCH: studies reviewed this week - 24 August 2020 to 31 August 2020

TRAINING: No Additional Benefits of Block- Over Evenly-Distributed High-Intensity Interval Training within a Polarized Microcycle

I've shared a study in the past showing that a 12-week block periodisation training plan was more beneficial than a traditional plan. This study aimed to investigate the "responses to block- versus evenly-distributed high-intensity interval training (HIT) within a polarized microcycle". The two training methodologies being compared were:

  • Twenty well-trained junior cross-country skiers completed two, 3-week periods of training (EVEN and BLOCK) in a randomized, crossover-design study.
  • In EVEN, 3 HIT sessions (5 × 4-min of diagonal-stride roller-skiing) were completed at a maximal sustainable intensity each week while low-intensity training (LIT) was distributed evenly around the HIT.
  • In BLOCK, the same 9 HIT sessions were completed in the second week while only LIT was completed in the first and third weeks.

The findings were that:

Pre- to post-testing revealed no significant differences between EVEN and BLOCK for changes in resting salivary cortisol, testosterone, or IgA, or for changes in muscle capillary density, fiber area, fiber composition, enzyme activity (CS, HAD, and PFK) or the protein content of VEGF or PGC-1α.

Neither were any differences observed in the changes in skiing economy, [Formula: see text] or 600-m time-trial performance between interventions.

These findings were coupled with no significant differences between EVEN and BLOCK for distance covered during HIT, summated HR zone scores, total sRPE training load, overall pREC or overall recovery-stress state.


PRACTICAL TAKE AWAY - block training may not be superior to evenly distributed training. However, it is not inferior. I would suggest choosing the appropriate training regime for each athlete during each part of the season.




PHYSIOLOGY: Sacrificing economy to improve running performance—a reality in the ultramarathon?

This study is a fantastic look at practical factors and considerations in ultramarathons that may differ from marathons. The authors explain the differences between marathon and ultramarathon economy factors as follows:

It has been argued that an exceptionally low Cr (cost of running) in marathon distances partly explains the supremacy of East African runners in the marathon, perhaps by delaying glycogen depletion and reducing thermal stress (13). But we believe that the lower exercise intensity in ultramarathons makes these parameters less important, whereas musculotendinous and osteoarticular damage is crucial for F (fraction of VO2 Max achieved).

Herewith, we propose that certain measures that actually increase Cr may be more than offset through gains in F in ultramarathon running, and such a balance is essential for performance optimization.

The authors recommend a number of areas where ultramarathon considerations may be different to marathon running:

Flexibility - flexibility training before an intense eccentric exercise attenuates exercise-induced muscle damage. Compliant legs may also limit low-back pain and the work of bouncing viscera, which may potentially reduce gastrointestinal symptoms.

Leg mass - although drastically increasing internal work when running at 20 km/h as for elite marathon runners, large thighs and calves are nevertheless less detrimental at low speed (8–12 km/h for the best runners in competitions lasting 15–24 h) compared with high speed and may even have advantages in terms of resistance to muscle damage.

Stride frequency - lower stride frequency allowed an athlete to reduce loading rate and peak force, we speculated it was a way to limit mechanical consequences from this extreme running distance despite the detrimental effect of increasing Cr by 6%.

Shoes - foot fatigue from less cushioned shoes along with the reduced benefit of midfoot footstrike during descents mean that ligher shoes are not necessarily better for ultramarathons. Additionally, velocity and stride frequency are lower in ultramarathons, so heavier shoes affect Cr less in ultramarathons than in shorter distances.

Poles - the effects of poles on Cr may depend on several factors such as slope and pole mass (6, 25) but speed and stride rate may also be involved. As is the case for shoe mass, adding mass at the upper limbs is less detrimental at low stride rates, i.e., in ultramarathons.

The authors conclude that:

Strategies to minimize Cr are compulsory in running events up to the marathon distance, whereas minimizing damage to lower limb tissue, muscular fatigue, and symptoms associated with prolonged running through measures that can increase Cr becomes crucial in ultramarathons.

PRACTICAL TAKE AWAY - factors that affect marathon performance may not easily transfer to ultramarathons due to how different these events can be from normal road races. Be practical and think about what you actually need to successfully complete your event rather than following what you see marathon runners doing.




TRAINING: Factors related to successful completion of a 161-km ultramarathon

This practical study looked at the factors that limit or affected race performance for runners in 100 miles races. The authors asked "all entries of the 2009 Western States Endurance Run and the Vermont 100 Endurance Race were invited to complete a postrace questionnaire". The findings were:

From this study, we conclude that primary performance-limiting issues in 161-km ultramarathons include nausea and/or vomiting, blisters, and muscle pain, and there is a disturbingly high use of NSAIDs in these events.

PRACTICAL TAKE AWAY - while these factors may be difficult to deal with in a race, preparing appropriately using race nutrition, taking care of your feet, and training appropriate for the demands of the race will significantly improve your chances of finishing and finishing well.




TRAINING: Training Load and Performance Impairments in Professional Cyclists During COVID-19 Lockdown

At the beginning of the lockdown period I shared a large number of articles in this post about how to adjust your training. While it was important to try and limit detraining while also not putting our immune systems at risk, it was a challenge to understand how much adjusting training would impact performance. This study aims "to inform about the changes in training volume and intensity distribution and their effects on functional performance due to a 7-week home-confinement period in professional road cyclists."

The results of the study showed that the cyclists severely limited their training (compared to normal) and the impacts on performance were significant:

  • Total training volume decreased 33.9% during the lockdown.
  • Weekly volumes by standardized zones (Z1 to Z6) declined between 25.8% and 52.2%, except for Z2.
  • There were large reductions in best 5-minute and best 20-minute performance with losses between 1% and 19% in all the cyclists.

The authors concluded that:

Total indoor volumes of 12 hours per week, with 6 hours per week at low intensity (Z1 and Z2) and 2 hours per week at high intensity over the threshold (Z5 and Z6), were insufficient to maintain performance in elite road cyclists during the COVID-19 lockdown.

PRACTICAL TAKE AWAY - a large reduction (of a third) of training will have significant impacts on fitness. Keep this in mind during any period of reduced training whether it's planned or unplanned.

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