Sunday, May 17, 2026

Warming Up Body And Mind

Picture from Healthywomen.org
All of us are familar with warm ups. Before you run, exercise and especially before a race. You are trying to increase your core temperature, send more blood flow to the limbs and 'wake' the muscles up. Before a running race you may even try some race pace striding so the actual start of the race does not feel like a shock.

So I was surprised to read that combining mental and physical warm ups can improve running times. Curious? Please read on to find out more.

Researchers in that study investigated whether combining cognitive tasks with a standard physical warm up could improve 1-mile performance in runners. 25 runners (11 male, 14 females) with an average weekly mileage of 20 miles (32 km) and 5km personal best timing of 23:31 min were recruited for the study. Each runner completed 3 separate testing sessions.

First was with only a physical warm up which included a 1200m easy jog, 800m alternating 100m jogs and 100m strides and 3 minutes of active stretching drills. 

Next was the same physical warm up plus a low load cognitive task and finally same physical warm up with a high load cognitive task.

In the cognitive warm up conditions, the runners completed four 3-minute cognitive tasks before and between the physical components.These tasks targeted mental functions like switching between tasks, decision making, inhibiting responses to stimuli and memory. They were doing short bursts of focused mental work designed to activate the brain without exhausting it.
 
After that all the runners ran 4 laps of a 400m track with their watch face covered so that they could only rely on feel rather than constant pace feedback.

Ready for the results? The runners were faster after both cognitive plus physical warm ups compared to only doing the physical warm up. The  low load cognitive task improved 1-mile timing by about 8 seconds (2.3%),  while the high load cognitive task improved performance by about 11 seconds (2.8%).

The runners did not appear to muscle their way to faster timings since their perceived effort was lower after the combined warm ups and their average heart rate during the time 1-mile run was also lower. Their readiness to perform was higher, meaning the runners felt more prepared to run hard.
Stride length and cadence did not change meaningfully suggesting that performance boost was not explained by obvious mechanical changes.

Take home message? No, you do not need to download an app to challenge your cognitve skills before every workout or race. However, this study does suggest that the best warm up should prepare both mind and body.

Before you do your track interval sessions, time trials or short, hard and fast sessions or even up to a 5 km race, it may be useful to add a small cognitive task that perhaps include coordination games, quick reaction tasks, fast feet with visual cues to make you engage attention before you start running hard.

The important thing to note is dose. A few short mental tasks coupled with jogging, drills and race pace striding may help you feel sharper and more ready for your workout. A long, draining task may do the opposite.

This sharpens the nervous system rather than stressing your brain. Keep it brief and engaging and please try it in your training first before trying it on race day.

Reference 

Mortimer, H Dallaway N, Diaz-Garcia J et al (2026). Warming Up The Body And Mind: Bombined Cognitive And Exercise Priming Improves 1-Mile Time Trial Performance In Recreational Runners. Eur J Sp Sci. 26(5): e70163. DOI: 10.1002/ejsc.70163

Sunday, May 10, 2026

New Guidelines For Fueling

I was sharing with some my patients this past week how I found it amazing that Sebastian Sawe was able to consume 115 grams of carbs an hour in his sub-2 hour marathon. Previous recommended guidelines were between 60-90 grams an hour.

Lo and behold, a patient shared that in the Nice Ironman last year, Casper Stornes (1st place) and Kristian Blummenfelt (3rd) took 120 grams of carbs while running and up to 180 grams on the bike.

Intrigued by what he sent me, I found a recently published review article by Morton et al (2026) which revisits carbohydrate guidelines for endurance athletes. So are the previous fueling recommendations enough?

When training and/ or racing for prolonged periods, carbohydrate intake will spare liver glycogen while maintaining your blood glucose levels. Most importantly, it helps one to sustain higher intensities nearer the end of your race. When everyone else is going faster, you do not want to run out of fuel and slow down.

Fueling is not to just avoid bonking (or hitting the dreaded wall). It is also to delay the shift from using carbohydrates to fat. That shift is not bad, but when you are trying to go fast without carbohydrates it is going to be very difficult. Note that if you are doing Zone 1 or 2 for many hours (like in an ultra marathon) at low intensities, then this shift may not occur.

When one consumes enough carbohydrates during endurance exercise, long ultra race, Ironman event etc, it delays the "crossover point".  This is when carbs stop being the predominant fuel due to glycogen depletion or low carb availability.

You can see from the diagrams above that if no carbs are consumed (0 grams each hour), this happens around 2 hours. With 45-90 grams/ hour, it delays the crossover point by 30-60 minutes. If 120+ grams/ hour of carbs are consumed, there is no crossover point since carbohydrates remain the predominant fuel source while exercising. At least not in cycling studies as the subjects exercised at 90 percent lactate threshold for 3 hours. It may still occur in longer races.

For runners, the review looked at elite male marathoners with personal bests under 2:30 hrs. They completed a 2 hour treadmill protocol close to marathon race intensity while consuming 60, 90 or 120 grams of carbs each hour. 

Those who ingested 120 grams used more of the ingested carbs leading to higher carbohydrate oxidation. They had a roughly 3 percent improvement in running economy compared to 60 grams per hour. There was also greater carbohydrate contribution to total energy expenditure late in the run. Now you know why Sabastion Sawe never slowed down in his sub-2 hour London marathon. 

There's a catch. Gastrointestional (GI) symptoms were also higher at 120 grams/ hour. Nausea, stomach fullness, and cramping were worse in the highest carb intake. More carbs may offer an advantage, but only if your gut can absorb and tolerate them.

The researchers say that runners should use 90 grams of carbs or more per hour as a realistic target for long, hard events. For trained athletes, the range may extend closer to 120 grams per hour. Fueling should be treated like a trainable skill, provided the gut has been trained to handle it.

Runners will find it more challenging compared to cycling since it's much easier to eat on the bike. All the moving, reduced blood flow to the gut, heat stress may lead to higher rates of GI distress.

This is an exciting review for fueling, but do note that most of the research comes from cyling, male athletes and in controlled lab settings. Female athletes are under-represented as well as real world running/ racing conditions.

My takeaway message? For some of you runners, 90-120 grams/ hour will most certainly help your times. Others may benefit from 60-75 grams/ hour. For other runners, it may be just progressing from under-fueling to consistently fueling and getting a personal best no matter how many grams of carbs that may be.

Reference

Morton JP, Fell JM, Gonzalez JT et al (2026). From Metabolism To Medals: Contemporary Perspectives And Revisiting Carbohydrate Guidelines For Fueling Endurance Athletes During Exercise. J Nutrition. 156(5). DOI: 10.1016/j.tjnut.2026.101442

Sunday, May 3, 2026

Sub 2 Hour Marathon

Back in 2017, renowned sports scientist Dr Ross Tucker wrote that a sub 2 hour marathon was unlikely to occur for generations. Then Nike introduced the Breaking 2 project which resulted in Eliud Kipchoge running under 2 hours albeit in a paced setting, not in an official race. 

The 2 hour barrier was finally broken last week at the London marathon when winner Sabastian Sawe and runners-up Yomif Kejelcha achieved the breakthrough, the latter running only his first marathon.

The podium
Sawe beat the previous world record by 65 seconds, finishing in 1:59:30 hrs. He ran an amazing negative split, 60:29 for the first half and the next half in 59:01 min. Kejelcha finished 2nd in 1:59:41 hours. The race was so fast that third place finisher Jacob Kiplimo also broke the previous world record (set in 2023) by 7 seconds. He clocked 2:00:28 hrs.

What lead to the breakthrough? Perhaps due to a "perfect storm" or convergence of many of the following factors. 

Sawe's team said he was running in excess of 200 km a week in the 6 weeks leading up to London, with a maximum of 241 km (150 miles). The volume of his training runs is likely an important factor for him to break 2 hours. Not many elite runners can tolerate that sort of volume, especially when most of it is done at low intensity (or Zone 1). High training volume done at relatively low intensity (Zone 1) is associated in faster marathon performances (Muniz-Pumarez et al, 2024).

Sawe's 5 km splits from 30 km onwards were superb. 30-35 km : 13:54 min, 35-40 km : 13:42 min. His final 2.2 km was 5:51 min. His 24th mile was 4:12 min - the fastest single mile ever run in a marathon. As the finishing line beckoned, he was still accelerating. No way he could have done this if he was not fueling well.

Sawe's nutrition was exceptional. I'm not plugging names here, in fact I've not even tried their products, but Sawe is a Maurten athlete. Elite athletes train their gut take up to 120 grams of carbs while competing without GI distress. The previous recommendation was 60 grams per hour previously. Sawe's reported intake was 115 grams an hour. Maurten's research team was with Sawe in Kenya for 32 days across 6 trips between last year and this April to train his gut to absorb that amount. 

Please note that 120 grams of carbs are NOT recommended for the recreational athlete. That is probably why cycling races and marathons are getting faster since there is no depletion in carbohydrate levels.

Sawe also used sodium bicarbonate (also from Maurten) to buffer his lactic acid build up during the race. He took the sodium bicarbonate early since it peaks in the bloodstream  roughly 60-90 minutes after ingestion so the timing of 2 + hours before the race would put peak buffering capacity at the start.

What about his shoes? Adidas says those were the fastest and lightest super shoes ever made. Actually, Adidas had a great day as 4 of the top 5 men were wearing the same Adizero Adios Pro Evo 3. It weighs 97 grams (for men's size 9), 30 percent lighter than its predecessor with a stack height of 39 mm (below the 40 mm limit by World Athletics). 

The Lightstrike Pro foam used is 50 percent lighter than the previous version, along with the carbon plate. Research suggests that the foam and carbon plate can affect the "spring like" bounce of the body as the foot strikes and leaves the ground. The shoes help to store and release energy and acts like the runner is pushing off a springboard so less energy is needed for the run.

London is considered a relatively fast course (though not as fast as Berlin) and the weather conditions was between 13-17 degrees Celsius, close to ideal.

There you have it, exceptional athlete physiology, high mileage training without injury, efficient biomechanics, super shoes , optimized fueling and favorable conditions. The recipe for success for running marathons.

Reference

Muniz-Pumares D, Hunter B, Meyler S et al (2025). The Training Intensity Distribution Of Marathon Runnersd Across Performance Levels. Sports Med. 55: 1023-1035. DOI: 10.1007/s40279-024-02137-7