Muscle oxygen saturation and iliac artery flow limitation with Jem Arnold | EP#358
That Triathlon Show
The Curvilinear Response Athletes
It tends to be these kind of categories of, you know, fitness level or training status. Leanness, let's say, or out of pose tissue. And then sex, which I think is part of that out of pose tissues story. But absolutely, like, we see this curvilinear response in, well, we had a male athlete who was,. you know, VO2 Max was 70 plus. So yeah, no, it does make sense, definitely.
Jem Arnold is a physiotherapist, coach and PhD student. Currently, his main research focus is investigating FLIA: blood flow limitation of the iliac artery, a condition that affects certain athletes even at the very elite level, sometimes with surgery as the end outcome. Jem is also very involved and knowledgeable in using NIRS (near-infrared spectroscopy) to measure muscle oxygen saturation (SmO2). We dive deep into how using NIRS and SmO2 can inform workout execution as well as training interventions and athlete profiling.
IN THIS EPISODE YOU'LL LEARN ABOUT:
-What is NIRS and what is muscle oxygen saturation?
-The balance of oxygen delivery (to the capillaries surrounding muscle tissue - supply) and extraction (by the muscles from the capillaries - demand)
-NIRS testing protocols, and how it relates (and does not relate) to oxygen uptake (VO2) and lactate measurments
-Using NIRS to profile athletes
-Using NIRS in high-intensity workouts to optimise interval execution
-Blood flow limitation of the iliac artery (FLIA) - what is it, and what is its prevalence among athletes
-Risk factors for FLIA
-Current detection and diagnosis methods of FLIA, as well as treatment options
-How Jem's research aims to find methods by which FLIA detection can be improved
SHOWNOTES:
https://scientifictriathlon.com/tts358/
SCIENTIFIC TRIATHLON AND THAT TRIATHLON SHOW WEBPAGE:
www.scientifictriathlon.com/podcast/
SPONSORS:
ROKA - Exceptional quality triathlon wetsuits, trisuits, swimskins, goggles, performance sunglasses as well as prescription eyeglasses and sunglasses. Online vision test for prescription updates and home try-on options available for eyeglasses. Ships from the US, UK and EU. Trusted by world-leading athletes such as Lucy Charles-Barclay, Javier Gómez Noya, Flora Duffy, Morgan Pearson, Summer Rappaport and others in triathlon, cycling, speed skating, and many more. Visit roka.com/tts for 20% off your order.
ZEN8 - The ZEN8 Indoor Swim Trainer is a unique swim bench that allows you to improve technique, power, and swim training consistency. With the trainer you can do specific power and technique work, including working on your catch and your core activation, and it makes it easier to stay consistent even when you can't go to the pool. Get the special Zen8 x TTS bundle including the swim bench and a number of Zen8 training plans and on-demand workouts on zen8swimtrainer.com/tts.
LINKS AND RESOURCES:
- Jem's Twitter, email, and his blog Sparecycles
- Muscle Oxygen Saturation (SmO2) with Roger Schmitz | EP#85
- What types of intervals are most effective? A scientific analysis with Michael Rosenblat | EP#243
- Applied triathlon science with Olav Aleksander Bu (Norwegian Triathlon Olympic team) | EP#264
- Moxy - well-established NIRS device
- Train.Red - another NIRS device also used and recommended by Jem
- Comparing the Respiratory Compensation Point With Muscle Oxygen Saturation in Locomotor and Non-locomotor Muscles Using Wearable NIRS Spectroscopy During Whole-Body Exercise - Yogev et al. 2022
- A longitudinal study on the interchangeable use of whole-body and local exercise thresholds in cycling - Caen et al. 2022
- Thresholds, Constructs, and Confidence Intervals - blog post by Jem
- Why is there Two Different Moxy Monitor SmO2 Profiles? w/ Jem Arnold - UTH1 - Upside Strength Podcast
- Maxima MC self-check questionnaire for FLIA (flow limitation of the iliac artery)
- Short- and long-term results of operative iliac artery release in endurance athletes - van Hooff et al. 2022
- Rejuvenated and recharged: Tayler Wiles eyeing return to the pro peloton after surgery - Velonews article
- Feature: Arterial disease and cycling - Velonews article
- Cyclists' Iliac Syndrome - Interest group - Facebook group
- Cyclist Alliance - List of international vascular specialists with experience in FLIA
RATE AND REVIEW:
If you enjoy the show, please help me out by subscribing, rating and reviewing: www.scientifictriathlon.com/rate/
CONTACT:
Want to send feedback, questions or just chat? Email me at mikael@scientifictriathlon.com or connect on Instagram, Facebook, or Twitter.
SPONSORS:
- Precision Fuel & Hydration produce our favourite gels, sports drinks, and electrolyte and carbohydrate products here at That Triathlon Show and Scientific Triathlon. Use the free Fuel & Hydration Planner to get a personalised plan for your carbohydrate, sodium and fluid intake in your next event, and get 15% off your first 2026 order by using the code TTS2026 at checkout.
- Rouvy is hands down the most complete indoor cycling platform for triathletes. Among their thousands of beautiful bike courses from all around the world, all filmed in stunning quality, they have over 75 IRONMAN and IRONMAN 70.3 race courses plus 20+ Challenge Family courses, so you can pre-ride your race from home. Real gradients, real visuals, and real feel! Head to rouvy.com and use the code TTS to get your first month free on top of a 7-day free trial.
- Effortless Swimming produce the best swim goggles for triathletes and open water swimmers. Their NanoClear anti-fog lenses give you clear, fog-free vision that lasts and doesn't wear off. Don't let foggy or leaky goggles ruin another swim. Go to shop.effortlessswimming.com and use the code TTS15 to get 15% off your goggles, and get a free two-month Effortless Swimming course membership.
Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.
The AI-powered Podcast Player
