Should You Train When Sick?

It depends! According to an MD. Plus: Is there a more aerodynamic cadence?

Good morning everyone,

After a few big days of training, I made the call to take a full day off yesterday instead of doing the workouts I had on my schedule. To be fair I’ve had a solid amount of work behind me, but my body started to talk, and I had to listen. And with a race in less than two weeks it’s probably time to start giving the body some rest and let it absorb the fitness!

In today’s edition: 

  • 🤒 Should you train when you’re sick? It depends!

  • 🥊 Fight inflammation with these antioxidant-rich veggies.

  • 🚴 And is there a more aerodynamic bike cadence?

Thanks for being here,

-Matt Sharpe, newsletter editor

Headshot of Matt Sharpe

Have a triathlete in your life who can't stop swimming, biking, or running? Fire this off to them. Forwarded from a friend? Sign-up for free. 


Should You Train When You’re Sick? It Depends! According To This MD

Dr. Jeffrey Krebs, MD FACP is a board certified Internal Medicine specialist who has been practicing for over 35 years. He is a former competitive figure skater, a 7-time Ironman and multiple 70.3 finisher, an elite Age Group runner who has raced Boston Marathon 8x with #9 coming up this year and will be competing in his third Age Group World Marathon Championship later this year in Sydney, Australia. He is a certified swim instructor and a run coach.

An article from Men’s Health Magazine was recently referenced in The Tempo titled “Should I Workout If I’m Starting To Feel Sick.”  This brief article suggests that exercise boosts the immune system and infers that it is ok to train when ill.  I take issue with some of what the article states and would like to clarify a few things. 

First of all, I would like to distinguish between viral and bacterial illnesses. Bacterial infections almost always require a doctor’s visit and antibiotic therapy. Far and away, however, the most common infections that we deal with are viral. When we talk about the common cold, upper respiratory tract infections (URI), “the flu,” etc., we are talking about viruses.

  • You are likely familiar with Influenza Virus, Coronavirus (causing COVID-19), and RSV but there are also Adenoviruses, Rhinoviruses, and a lot more.

  • When we get infected, the viruses enter our cells, often without being deactivated or destroyed. Their goal is to replicate, exit the cells, and infect more cells.

Once we are infected, our immune systems go to work. We develop fevers to raise our core temperature to destroy the virus. In this case, the fever is good. As the viral infection continues, we may develop chills, sore throat, headache, muscle aches, nasal congestion, cough, sneezing, watery eyes, and with some viral infections, nausea, vomiting, and diarrhea. A lot of what we experience is a result of our immune system at work and not necessarily a direct result of the virus. 

Viral infections may be minor or they may be serious. Knowing when to seek medical attention is important. You should see a physician for prolonged fever, shortness of breath, a decrease in your oxygen saturation (SaO2, aka O2 Sat.), elevated resting pulse, deep cough, cough with the production of dark brown, dark green or bloody sputum, persistent nausea, vomiting or diarrhea, blood in your stool or vomiting blood. In addition, if you test positive for COVID, seek medical attention as soon as possible since you may be a candidate for anti-viral therapy.

Many of us as endurance athletes have monitoring devices (Garmin for example) that can monitor our pulse and O2 sat, making it easy to know when something is amiss.  Any O2 Sat below 90% is an indication to see a physician but I argue that if your O2 sat is normally in the high 90’s% and it drops to the low 90’s% and stays there, that would be an indication to seek medical evaluation ASAP. If your resting pulse is normally in the 50’s and now it is in the 70-80’s, that is significant.

As endurance athletes, we are trained to monitor our bodies. We need to use the info given to act accordingly. This is often difficult because we love to train, love to complete every workout, and love to check those “boxes.”

  • You need to know that there are times when we benefit more from rest than we do by performing a suboptimal workout that does not enhance our training.

  • Why our bodies need resources to fight illness.

  • How long should you stop training with a viral illness?

  • And when it’s actually OK to train while sick!

Do you train while ill? What are your strategies for managing illness?

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🥬 Veggies against inflammation: Inflammation in your body isn’t necessarily a bad thing, but when it becomes chronic that’s when serious health issues can crop up. These ten veggies will help you fight inflamation and perform your best. [Eat This Not That]

🏆 Your best run is possible: Have you been struggling with difficult injuries? Exakt Health is here to help! Exakt's expert-designed injury recovery plans work with you to help you recover from Achilles tendinopathy, plantar fasciitis, and so much more. Want to prevent injuries? Exakt has world-class injury prevention plans to keep you performing at your best. Check out the Exakt Health app, try it free for 7 days, and save up to 40% with "THETEMPO."*

🚴 Aerodynamic cadence? Is there a more aerodynamic bicycle cadence? Apparently! This informative and intriguing video shows how riding at low (60 RPM), medium (90 RPM), and high (120 RPM) affect your aerodynamics. In reality, we wouldn’t recommend training/racing at 60 or 120 RPM! [Alex Dowsett]

👠 Racing shoes ranked: For some, race season is just around the corner. And maybe its time to jump into a new pair of racing shoes. This video has a great breakdown of many of the top shoes. [Believe in the Run]

🤣 This IRONMAN can(‘t): The question is earnest enough. Can a 55-year-old, who smokes three packs a day, swims the dog paddle, and plans to run in Converse high tops finish a full-distance IRONMAN? It’s definitely a troll question, but the responses are just as good! [Reddit]

🎢 Olympic qualification heats up: If you’re following the drama that comes with Triathlon Olympic qualification be sure to listen to this week’s episode of “Chasing the Burn.” Chelsea and her guest host (your newsletter editor), make sense of wild races in Quarteria, Portugal and in Hong Kong! [Chasing the Burn]

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Bonus points for this one with the Jumanji clip!


Here are Tempo readers’ thoughts on the rise of pro racing shifting to a series format.

Reader: This is, of course, personal preference, but I always prefer league vs one game. In one day racing everyone can have great (or bad) one off performance. Take NBA finals as an example. Winning 4 out of 7 largely removes "bad luck" factor.

Reader: Athletes have to peak. They are not F1 cars. World championships are races athletes will peak at. They will be in their best shape.

Reader: Come on, Matt. Your critique of the T100 series is tempered by your desire to also be part of it. You raised your hand several times to be a wildcard. As has been said on many podcasts, this is good for the sport. I'm not sure why you need to poop all over the T100 series. As an amateur triathlete, watching the women race the T100 was spectacular. I also watched the entire men's race. The post-race materials being put out on YouTube are also really stellar. Athletes are not voting with their feet about the entire series -- Singapore is a really heavy lift for travel. You should know that they have to weigh their options in order to keep racing all season. Let's have a little more balance, do you think, please? I'm so tired of pundits declaring PTO and T100 are dead before it's really even begun. Yes, it gets you more clicks to be contrarian, but it definitely isn't a balanced view.

Tempo: Fair points all around! Although I still believe that it was a mistake by T100 to not have all their best available athletes lined up for the first races of a make-or-break season. At the end of the day, we’re highlighting the series and providing them with a valuable resource - attention.

Reader: My concern is that after a few races we will start to suffer from “big name fatigue” and these “all star lines ups” will have been normalized. Some of that World Championship magic will have been lost. Not to mention, many top athletes will be injured along the way and won’t even make the grand finals of the year.

Reader: Definitely a fan of the season format. I think we will see how both series do mid year. Miami was so early for the pros, and Oceanside has the history as the start of the year.

Reader: I like to watch several races during the year to see how the different dynamics play out . I also like watching the performances on different types or courses. Kona is iconic but it suits a perticular type of racer and it really is too long watch as a spectator. The short course races I prefer because the athletes are faster and the dynamics are more exciting.

Reader: I believe this is a stepping stone to a greater single series. The competition between the two series will improve the end product faster than a monopolistic one. Eventually, one of the series will prevail and the precedent will have been set.

Reader: I think a season-long narrative is intriguing and provides context for the big events and makes them even more compelling as a result. I enjoyed watching T100 Miami, but it's the Championship races that are the real draw.


IRONMAN 70.3 Geelong, Australia

World Triathlon World Cup Hong Kong


College champions: Santa Barbara’s city college has a new triathlon team, and the motivated club founder Ava Smith has big ambitions. [The Channels]

Listen to Tim: Timothy Reardon is a world-class 75-year-old triathlete who competes globally. His advice for getting the most out of yourself? Staying consistent. [Yahoo Sports]

Vietnam triathlon success: Over 500 triathletes from 19 countries competed in FesTrival Binh Thaun. It was a successful weekend that showcased the beautiful scenery to locals and those from abroad. [Vietnam Plus]

  • Major start lists reveal series’ battle for talent. Plus: incredible new protein science.

  • IRONMAN hopes data drive turbocharges profit, and how to train your gut. 

  • IRONMAN updates 2024 rules, and this magic muscle will help keep you injury free.

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