Martin MacInnis

Dad, assistant professor, exercise physiology researcher. Interested in muscle metabolism, hypoxia, nutrition, wearable technology, and science education.

[Journal of Applied Physiology @japplphysiol]

Research Article by RS Ghitter (@MartinMacinnis) #Sexdifferences in the power-duration relationship for dynamic #knee extension are largely explained by #muscle size
https://t.co/kh0YyyrKNP

[Journal of Applied Physiology @japplphysiol]

Research Article by @ZhangJens et al. (@MartinMacinnis @UCalgary) #Neurophysiological and #perceptual responses to consecutive days of exhaustive #highintensityinterval #cycling are dissociated
https://t.co/d4L3ibfLhQ

[Hilkka Kontro @HilkkaKontro]

How to quantify the training load of higher intensities and sprints, separately from aerobic training load, simply from power data? We suggest a 3D strain score (alternative to the "1D" TSS/TRIMP/work -> fitness paradigms) to capture the nuances of training CP, W', and Pmax.

[Technavance @technavance]

Reminder: Less than 8 weeks left to apply! ⏰

There’s still time to apply for the 2nd Technavance Student Travel Award. If you’re presenting research at a conference in 2026, you could win up to $500 to support your travel.

👇 Apply here:
https://t.co/sJnNO0Ybmp

[Alex Hutchinson @sweatscience]

This wasn't on my bingo card for 2025 - but yes, I'm giving a lecture hosted by TPL's famed Arthur Conan Doyle Collection on Nov 29!

I'll be talking about blank spaces, armchair exploring, and the pursuit of "useless knowledge." Come check it out!

[FloTrack @FloTrack]

Dunfee has done it! 🥇

After narrowly missing gold in multiple global championships, 34-year old Evan Dunfee is the 2025 35km race walk World Champion. He finished in 2:28:22, ahead of Brazil’s Caio Bonfim in 2:28:55, and Japan’s Hayato Katsuki in 2:29:16.

#WCHTokyo25 coverage presented by @brooksrunning

[CBC Olympics @CBCOlympics]

WORLD CHAMP 🇨🇦🥇

With grit and determination, @EvanDunfee wins Canada's first medal of #WCHTokyo25 and it's a GOLD 🙌

[Devin Heroux @Devin_Heroux]

Evan Dunfee just grabbed a Canadian flag from fans lining the track.

He’s now charging into the stadium.

It’s going to be go gold. Incredible.

[Jem Arnold @jem_arnold]

When does resistance exercise become endurance exercise? 🏋️↔️🏃

It might depend on the critical occluding tension in our muscles 💪🩸

🧵/ 📚link👇

A Critical Occluding Tension Phase Transition Occurs Between 30-40% 1RM in Dynamic Knee Extension Exercise

[Experimental Physiology @ExpPhysiol]

Nominations for our Inaugural Review Prize are open!

🏆 The winner will receive £1000, and publish a Review Article in our journal.

📆 Nominations are open until 31 July 2025.

📜 Find out more about how to apply and submit your proposal: https://t.co/FF0oMFKKwQ

[Brian Carson @DrBPCarson]

🚨PhD alert 🚨 looking for interested candidates to apply for a fully funded PhD in Physical Activity, Sedentary Behaviour & Metabolic Health of new parents. For enquiries DM or brian.carson[at]https://t.co/ZJEQS0oXFh & include CV. Must be willing to work on app over next 3 weeks

[Alex Hutchinson @sweatscience]

1953: Hillary & Norgay climb Everest with O2, Bannister just misses sub-4 with lapped pacer

2025: 4 Brits climb Everest with xenon, Kipyegon aims for women's sub-4

My thoughts on history, fair play, and the problem when everything becomes a competition.
https://t.co/penguMdVU3

[The Hornberger Lab @HornbergerLab]

1/10 Excited to write this thread summarizing our new paper in @NatMetabolism, which identifies a potentially critical part of the signaling pathway that drives skeletal muscle growth in response to resistance exercise!
Free link https://t.co/JWca6dVU2a
#Myotwitter @NIH_NIAMS

[Australian Physiological Society @AuPhysiolSoc]

🎉 The Australian Physiological Society turns 65 in 2025!
Add to your calendar the annual meeting, 23–26 Nov at Western Sydney Uni (Parramatta), to celebrate 🧠🔬
Cutting-edge science, networking & more!
#AuPS2025 #Physiology #STEM #AusSci #65YearsStrong

[Technavance @technavance]

🔬 Meet Rachel Ghitter, a grad student at the @UCalgary! Her research explores sex differences in muscle performance. She’s up to win our Student Travel Award and is presenting at the 2025 @csep_scpe annual conference! Vote for Rachel here 👇

https://t.co/sJnNO0Ybmp

[Hilkka Kontro @HilkkaKontro]

New! We measured rates of hemoglobin synthesis in trained and untrained individuals and found them to be similar despite some earlier work showing shorter RBC lifespan in athletes. @MartinMacInnis https://t.co/RKzxSu8YYM

[Martin MacInnis @MartinMacInnis]

New paper on using D2O to measure hemoglobin synthesis rates in humans! We explained this application of D2O in @Acta_Physiol https://t.co/h4XwxJoViS and use it here to show no influence of training status. Reach out if you're interested in this method.

[Hilkka Kontro @HilkkaKontro]

New! We measured rates of hemoglobin synthesis in trained and untrained individuals and found them to be similar despite some earlier work showing shorter RBC lifespan in athletes. @MartinMacInnis https://t.co/RKzxSu8YYM

[Martin MacInnis @MartinMacInnis]

Our review argues that cardiorespiratory fitness needs to be matched between males and females when investigating sex differences

[Journal of Physiology @JPhysiol]

Thomas R. Tripp (@uofcknes) et al. discuss controlling for cardiorespiratory fitness in exercise physiology studies of sex as a biological variable ✍️ 🏃

🔗 Read the #TopicalReview here: https://t.co/2wLbWViQ1M

[Journal of Physiology @JPhysiol]

Thomas R. Tripp (@uofcknes) et al. discuss controlling for cardiorespiratory fitness in exercise physiology studies of sex as a biological variable ✍️ 🏃

🔗 Read the #TopicalReview here: https://t.co/2wLbWViQ1M

[Nathan Hodson @nathanhodson5]

🚨Pls Retweet/Share! 🚨15-month postdoc position available with me to investigate the dysregulation of anabolic and autophagic skeletal muscle cell signaling in obesity! Funded by @acmedsci and in collaboration with @Metabolcenter. See link for details https://t.co/0ryrxsYYMi