Preview Mode Links will not work in preview mode

303Endurance Podcast

May 28, 2022

Welcome to Episode #338 of the 303 Endurance Podcast. You are listening to your weekly connection to coaches, experts, and pro athletes to help you reach your endurance goals. We're your hosts coach Rich Soares and 303 Chief Bill Plock. Thanks for joining us for another week of endurance interviews and discussion.


Show Sponsor: UCAN

Take your performance to the next level with UCAN Energy and Bars made with SuperStarch®  UCAN uses SuperStarch instead of simple sugars to fuel athletes.  UCAN keeps blood sugar steady compared to the energy spikes and crashes of sugar-based products.  Steady energy equals sustained performance!


Use UCAN in your training and racing to fuel the healthy way, finish stronger and recover more quickly!  Use the code 303UCAN for 20% off at or



In Today's Show

  • Training Discussion: Lactate Threshold Test
  • Endurance News
    • 2022 Escape from Alcatraz Triathlon
    • New Garmin Varia RCT715 tail light has a camera to record your crashes
    • Why Running at Night Feels Harder
  • What's new in the 303
    • Ragnar Snowmass June 9-10
    • Without Limits Productions Inglis Cup - SHIMANO Cyclocross Series
  • Video of the Week
    • Ragnar Snowmass


Training Discussion: Lactate Threshold Test


Last couple of weeks we have discussed how regular testing and consistency at the correct intensities improve performance. To improve our endurance, we want to be more efficient at an aerobic intensity. To improve our speed, we want to have a higher anaerobic capacity. Besides doing "field testing" like the Swim CSS, Bike FTP and Run TT, one scientific way to test is how well the body processes muscle lactate. If you've ever done a Lactate Threshold Test (LTT), here's how the test administrator interprets the lactate measurement to determine your training zones.


The LTT is performed by starting the athlete a warmup at a very easy intensity. We'll use the run discipline for this example. The athlete will walk on a treadmill for 10 minutes before starting the test and once the test starts, the intensity is increased every 2 minutes. At the beginning of the 10 minutes, the test administrator takes 4 metrics - pace, rate of perceived exertion (RPE), heart rate (HR) and lactate millimoles per liter of blood with a blood sample and lab kit. The lactate compared to the pace is the primary metric and the HR and RPE are secondary but useful to confirm and interpret the data. The administrator takes those same 4 metrics at the end of the 10 minutes and every 2 minutes there after. Every 2 minutes the treadmill pace is increased by 30 seconds of pace (11:00, 10:30, 10:00, 9:30 and so on).


There are two key inflection points the test administrator is looking for. When the intensity is increased and the lactate level remains the same as the previous level means that the subject athlete is predominantly aerobic (zones 1-2). When the lactate level increases and levels out after each increase the athlete is in between aerobic and anaerobic (zone 3). When the lactate level continues to rise without an increase to intensity, the athlete is above lactate threshold (zone 4-5).


Our News is sponsored by Buddy Insurance.

Buddy Insurance gives you peace of mind to enjoy your training and racing to the fullest. Buddy’s mission is simple, to help people fearlessly enjoy an active and outdoor lifestyle. 


Get on-demand accident insurance just in case the unexpected happens. Buddy ensures you have cash for bills fast.  This is accident insurance not health and life insurance.  Go to and create an account.  There's no commitment or charge to create one.  Once you have an account created, it's a snap to open your phone and in a couple clicks have coverage for the day.  Check it out!


Endurance News:


Olympians and World Champions Lead Field of Professional Triathletes Set to Compete in 2022 Escape from Alcatraz Triathlon

May 26, 2022

Reigning Champion Ben Kanute Returns to Attempt Fifth Straight Win

SAN FRANCISCO – (May 26, 2022) /ENDURANCE SPORTSWIRE/ – IMG, a global leader in sports, events, media and fashion, today announced the pro field for the 41st Escape from Alcatraz Triathlon, set to take place June 5, in San Francisco. The line-up includes Olympian Ben Kanute (USA), 2016 IRONMAN World Champion Holly Lawrence (GBR), seven-time IRONMAN Champion Ben Hoffman (USA), and more.


Four-time Escape from Alcatraz Triathlon Champion Kanute returns to defend his title this year. He represented the United States in the 2016 Olympics and recently took first place in the 2021 IRONMAN 70.3 California, second place in the 2021 IRONMAN 70.3 Texas and third place in the 2022 Clash Miami.


“Winning my fourth straight win was special and now having the opportunity to go for a fifth seems unreal,” said Kanute. “I cherish every Escape win and never take them for granted as this can be an unforgiving course. Escape is one of my favorite races and it is even more special this year since my dad, brother and coach are all racing!”


The field also includes 2016 Escape from Alcatraz Champion Holly Lawrence (GBR). Lawrence returns after placing second in the 2021 Escape from Alcatraz Triathlon. She is also a 14-time IRONMAN 70.3 Champion and the 2016 IRONMAN 70.3 World Champion. She recently took first place in the 2021 IRONMAN 70.3 Des Moines and third place in the 2022 IRONMAN 70.3 California.


Jason West (USA) returns to attempt to overcome Kanute, after placing second in last year’s Escape from Alcatraz Triathlon. West recently took first place in the 2022 Sunbelt Bakery IRONMAN 70.3 North American Championship Chattanooga, first place in the 2021 IRONMAN 70.3 Memphis and first place in the 2021 IRONMAN 70.3 Des Moines.


Returning for her third Escape, Jackie Hering (USA) will attempt to move up the podium after placing third in last year’s Escape from Alcatraz Triathlon. Five-time 70.3 Champion Hering, recently took first place in the 2022 Sunbelt Bakery IRONMAN 70.3 North American Championship Chattanooga, first place in the 2022 Clash Daytona and second place in the 2021 IRONMAN 70.3 Memphis.


The pros will join 2,000 amateur triathletes for this annual event. The full list of professional triathletes set to compete in the 2022 Escape from Alcatraz Triathlon and stake their claim in the $50,000 prize purse includes:



Holly Lawrence (GBR)

Jackie Hering (USA)

Jodie Stimpson (GBR)

Daniel Lewis (GBR)

Megan Foley (USA)

Ginger Howell (USA)



Ben Kanute (USA)

Jason West (USA)

Ben Hoffman (USA)

Eric Lagerstrom (USA)

Brent McMahon (CAN)

Gregory Harper (USA)

John Dahlz (USA)

Austin Hindman (USA)


Triathletes will hit the water at 7:15 a.m. to embark on a challenging 1.5-mile swim from Alcatraz Island to the shoreline of Marina Green, an 18-mile twisting bike ride through the Presidio, and an 8-mile trail run out to Baker Beach and up the infamous 200-plus step Sand Ladder. To finish the race, triathletes will follow a path back under the Golden Gate Bridge, pass Crissy Field and finish on the grass at Marina Green. Fans can experience the excitement at Marina Green, where the swim exit, athlete transition area and finish line are easily visible. This year’s event will also feature the 2022 Escape Aquathlon on Saturday, June 4. For additional information, visit or follow @EscapeAlcatrazTri on Instagram and Twitter and on Facebook.


New Garmin Varia RCT715 tail light has a camera to record your crashes

The Varia’s high-definition camera will record everything behind you and its radar will alert you to approaching vehicles. Garmin has released the Varia RCT715, a new version of its tail light that features a high-definition camera to record any incidents out on the road.


The Varia RCT715 features the same radar technology as its predecessors. When paired with a Garmin bike computer or smartwatch, the Varia will alert users to vehicles approaching from behind up to 140m away. Garmin says the device can be paired with selected cycling apps such as Ride with GPS. This will enable users to overlay maps with the radar notifications.


Garmin claims the Varia RCT715’s tail light can be seen up to one mile away in daylight. The camera records continuously and will save footage if an incident is detected. Garmin says the Varia’s camera will “capture sharp, clear footage” at up 1080 pixels and 30 frames per second.


The camera will record constantly when the Varia is in use. If an incident is detected, via Garmin’s Incident Detection feature, the camera will automatically save footage from before, during and after the event. According to Dan Bartel, Garmin’s vice president of global consumer sales, this is to provide users with evidence of an incident “should they ever need it”.


However, the camera also provides more recreational functions, in line with how you might use a GoPro. Via the Garmin Varia app, users can access the video footage, transfer files and customise the camera’s settings, to do things such as overlay data, including speed and location.


Garmin says the use of the camera will be prohibited or regulated in some jurisdictions, adding that it is the responsibility of the user to know and comply with applicable laws and rights to privacy. While Garmin has added a camera to the Varia, it has retained the radar and tail light functionality of the device.


Like the previous Garmin Varia RTL515, the radar on the new version will still detect and alert users to vehicles approaching from behind to the same distance of 140m.


Similarly, the tail light on the new version is said to be visible up to one mile away in daylight, which is the same as the Varia RTL515. But while the RTL515 has a claimed battery life of up to 16 hours, the RCT715 has a shorter claimed battery life.


The Varia RCT715’s battery life is said to be up to four hours with radar and the tail light on ‘solid high’ or ‘night flash’, and up to six hours with the light flashing. The reduction in battery life is presumably because the camera is recording continuously.


Why Running at Night Feels Harder

An interesting new study by researchers at Sweden’s KTH Royal Institute of Technology, working with the Swedish military and colleagues in Slovenia. They’d noticed that soldiers on night marches seemed to burn more energy than would be expected from the physical demands of the mission, especially when wearing night-vision goggles that restrict peripheral vision. They wondered whether not being able to see forced the soldiers to alter their strides, sacrificing efficiency for stability, so they decided to test this theory.


The new study, published in the European Journal of Applied Physiology, had 15 volunteers do a series of ten-minute treadmill walks in four conditions: with and without a 56-pound pack, and with and without a blindfold on. The treadmill was set at a comfortable pace of around 30 minutes per mile, with a laser warning system to alert them if they were about to fall off the back of the treadmill.


The results showed that oxygen use (a proxy for energy consumption), breathing, and heart rate all increased substantially when wearing the heavy pack, as you’d expect. The surprise was that they increased by nearly the same amount when adding a blindfold. Here are the graphs of those three parameters, with (circles) or without (squares) the blindfold:


If you compare the circles on the left (i.e. blindfolded with no backpack) to the squares on the right (i.e. not blindfolded with a backpack), you see they’re almost the same. In other words, walking with a blindfold takes as much extra effort as walking with a 56-pound pack. To be precise, the backpack increased oxygen consumption by 20 percent, while blindfolding increased oxygen consumption 19 percent.


The explanation for this effect seems to be that the subjects adjusted their strides when blindfolded: their steps got 11 percent shorter and 6 percent wider, and they also lifted their feet 18 percent higher. Bear in mind that this is on a perfectly flat treadmill, so there are no bumps or potholes to avoid: this is just an instinctive response. It’s also worth noting that the effect probably isn’t just because they’re unfamiliar with the challenge of walking while blindfolded: a similar test of blind subjects found that they burned about 25 percent more energy while walking than sighted controls.


Of course, being blindfolded is significantly more disruptive than wearing night goggles, or simply being out at night in poorly lit conditions. That means the size of the effect is probably exaggerated. And walking is different from running. But it seems reasonable to assume that similar mechanisms are at work when you’re running in the dark—along with other, more subtle mechanisms like optic flow, which is the pattern of objects flowing through your vision as you move through space.


When you’re running or cycling in the dark, you can only see objects that are relatively close to you. That means that they appear in your field of vision only briefly before disappearing behind you, which corresponds to faster optic flow than you’d experience in daylight. A few previous studies, most notably those by Dave Parry and Dominic Micklewright of the University of Essex, have tried manipulating optic flow in virtual reality setups, making the scenery fly past more quickly or slowly than the speed of the treadmill or exercise bike. Sure enough, when optic flow is faster—as you’d experience in dark conditions—you feel like you’re moving faster, and any given pace feels harder.


There’s an interesting corollary to these findings about optic flow, as Parry explained to Runner’s World’s Scott Douglas back in 2012. “Running in an environment where most of the visual reference points you can see are close by, you experience a greater sensation of speed than when in an environment where your reference points are far away,” he said. That means running through a forest or through city streets will likely feel faster than running across an open field.


Ever since reading about those optical flow results, I’ve dismissed the gap between my actual and perceived pace during night runs as a quirk of how my brain estimates effort. During most of my runs, that gap doesn’t matter—but if I’m trying to do a tempo run or hard workout before sunrise, the slower pace can be a bummer. So I’ll take the new Swedish results as reassurance that night running might really be physiologically harder, not just a brain error—and if that’s what it takes to avoid tripping in the dark, I’ll accept the trade-off.


What's New in the 303:


Ragnar Snowmass



Ragnar Trail Snowmass-CO presented by Salomon brings you the perfect fusion of trail running, high-country camping, and Rocky Mountain beauty. Teams of 8 (or 4) will find their inner wild on three separate mountain trails, or “loops" that start and finish at Ragnar Village. Glacial valleys, snowcapped peaks, and blooming wildflowers set the scene as you make your way along rolling single-track. Though you may blame the altitude, in the end it will be the stunning mountain views that take your breath away. Conquer each climb and you'll be rewarded with panoramic views of the Maroon Bells -Snowmass Wilderness — not to mention a much needed downhill.


Without Limits Productions

May 13 at 8:30 AM  ·

This season we usher in a new era of cyclocross, but an era built upon the champions and friends who have defined excellence over its past 23 seasons.  We're proud to announce, on the 1-year anniversary of her tragic passing, the new Gwen Erffmeyer Inglis Cup for the SHIMANO Cyclocross Series - Women OPEN Series Champion!


Upcoming Multisport Events in Colorado (

Upcoming Classic Races in Colorado (


Video of the Week:

Ragnar Trail Snowmass - CO




Upcoming Guests:

World Champion Adventure Racer, Robin Benicasa with us today. Robyn is an award-winning keynote speaker, a 20+ year veteran San Diego firefighter, a 2014 CNN Hero, a Guinness World Record Endurance Kayaker, a best-selling author of "How Winning Works", and founder of The Project Athena Foundation, a non-profit dedicated to helping survivors of medical or other traumatic setbacks achieve their adventurous dreams.



Good luck to those racing Ironman 70.3 Chattanooga and Ironman Tulsa this weekend!

Thanks again for listening in this week.  Please be sure to follow us @303endurance and of course go to iTunes and give us a rating and a comment.  We'd really appreciate it!

Stay tuned, train informed, and enjoy the endurance journey!