Every distance runner and triathlete has felt the wheels slowly fall off late in a race. Late-race fatigue is multifactorial. Glycogen depletion, central fatigue, thermoregulation, dehydration, and neuromuscular fatigue across multiple muscle groups all play a role. But there's one specific component of the late-race fade that's grounded in solid biomechanics research, doesn't get the attention it deserves, and is one of the most trainable pieces of the puzzle.

In this episode, Kate walks you through what happens to your calves and Achilles tendon over the course of a long race, why this complex is so central to running economy, and the specific evidence-based strength training approach that can offset the late-race cost. This won't fix everything that goes wrong in the final third of a marathon or ironman, but it will fix one meaningful piece of it.

This episode is for runners and triathletes training for half marathon, marathon, 70.3, and Ironman distances who want to understand why their pace falls apart late in long races and what the research actually says about preventing it.

In this episode:

The deterioration of running economy and the concept of durability as the fourth determinant of endurance performance

How the Achilles tendon works as a spring and why muscle-tendon decoupling matters

The role of enthalpy efficiency in the soleus muscle

What happens when the Achilles tendon loses stiffness mid-run (Fletcher and MacIntosh 2018)

How calf fatigue redistributes propulsive work up the leg to the knee and hip (Sanno 2018, Nahan 2025)

How female runners may experience this differently (Quan 2021)

The Bohm 2021 protocol and the tendon strain threshold for adaptation

Plyometric programming for running specificity

The complete lower-body strength picture for long-distance athletes

Companion episodes available for the role of the calf and Achilles complex in runners and triathletes specifically, plus an upcoming dedicated calf training programming episode.

Key research referenced: Fletcher and MacIntosh 2018, Sanno et al. 2018, Nahan et al. 2025 (preprint), Bohm et al. 2021, Arampatzis et al. 2007, Quan et al. 2021, Melaro et al. 2021, Jones 2024.

If this episode helped, please subscribe, leave a rating, and share it with a training partner. Your support is what keeps this kind of research-grounded content going.

Kate Baldwin, PhD

The Distance Dr

Physiotherapist, sports scientist, strength and conditioning coach

Training plans look neat on paper. Real life does not always behave that politely.

In this episode of Distance Dr Daily, I talk through what to do when you are following a marathon, half marathon, triathlon or running plan and suddenly things change: you feel run down, you get sick, or an injury starts to niggle.

The big question is usually: do you catch up on missed sessions, swap things around, take a break, or just jump back into the plan?

I break this down into three common scenarios: fatigue or feeling run down, illness, and injury. We talk about when it may make sense to swap a session, when to reduce intensity, when to rest, and when symptoms mean you should stop and seek medical advice. I also cover why suspected bone stress injury is different, why altered gait matters, and why jumping straight back into hard sessions after a flare-up can backfire.

The goal is not to follow the plan perfectly. The goal is to make smart decisions so your body can actually adapt to the training.

In this episode:

• What to do if you wake up exhausted on interval day
• When to swap, reduce or skip a session
• Why you usually should not “catch up” missed runs
• How to modify training when you are sick
• How to return after time off or altered training
• How to think about pain during running
• When injury symptoms need medical advice
• Why your plan needs to bend before your body breaks

This is a practical episode for runners and triathletes who want to keep training moving without forcing the plan at all costs.

Easy Runs Are Not Junk Miles

Easy runs are one of the most commonly misunderstood parts of a running program.

They are meant to be easy, yes, but that does not mean they are throwaway runs. In this episode of Distance Dr Daily, I explain why easy runs matter, what adaptations they help support, and why letting them creep too hard can interfere with the rest of your training.

We cover how easy runs contribute to aerobic development, running load tolerance, fat oxidation, plasma volume, capillary and mitochondrial adaptations, and why doing them too fast can leave you carrying fatigue into the sessions that are actually meant to be hard.

I also explain how to use the Talk Test to check whether your easy runs are actually easy, plus a few simple signs that your easy days may be drifting too hard.

If your intervals, long runs, or key sessions are starting to suffer, your easy runs might be the first place to look.

In this episode:

• Why easy runs are not junk miles
• What adaptations easy running supports
• How to use the Talk Test
• Why easy runs creep too hard
• How “too fast” can affect fatigue, injury risk, and key sessions
• Signs your easy runs are no longer easy

Easy means easy, but easy still has a purpose.

On today's episode of The Distance Dr Daily with Dr Kate, she discusses how long runs are the cornerstone of marathon training, but most of the questions runners actually have, how far, how often, how hard, when to peak, and what to practise, don't always get answered clearly in a generic training plan.
I walk through five evidence-based considerations for getting your long run right, drawing on recent research and applying it practically for runners building toward a half marathon, marathon, or longer.
I cover:
How often to do your long run, and why every 7 to 10 days can work better for some athletes, particularly those who are injury-prone, postpartum, or new to marathon training.
How long your long run should actually be, based on what research shows works across different weekly training volumes, and why staying under 25 km may cost you on race day.
Where to place your peak long run in the training block, and how far out from race day it should sit.
How to progress your long run distance safely using the 10% rule, which applies specifically to your long run rather than your overall weekly volume.
How hard your long run should be, where marathon pace work fits in, and why it shouldn't be every week.
What to practise during the long run, including fuelling, hydration, cadence, and biomechanics under fatigue.
This is for runners who want to train smarter, not just harder, and who want to understand the why behind the long run rather than just ticking off the kilometres.

Study references:
Fokkema T, van Damme AADN, Fornerod MWJ, de Vos RJ, Bierma-Zeinstra SMA, van Middelkoop M. Training for a (half-)marathon: Training volume and longest endurance run related to performance and running injuries. Scand J Med Sci Sports. 2020 Sep;30(9):1692-1704. doi: 10.1111/sms.13725. Epub 2020 Jun 3. PMID: 32421886; PMCID: PMC7496388.

Knopp, M., Appelhans, D., Schönfelder, M., Seiler, S., & Wackerhage, H. (2024). Quantitative Analysis of 92 12-Week Sub-elite Marathon Training Plans. Sports medicine - open, 10(1), 50. https://doi.org/10.1186/s40798-024-00717-5

Generic running plans are not automatically bad. In fact, for many runners, they are affordable, accessible, and much better than making things up week by week. But the problem is that a generic plan does not know your injury history, your sleep, your training load tolerance, your work schedule, or how your body is responding.

In this episode of Distance Dr Daily, I explain how to make a generic running plan work better for you.

We talk about why individualised coaching is usually the gold standard, but also why generic programs can still be useful when you adjust them properly. I cover the two biggest things runners need to modify: their expectations and the program itself.

I also explain how I would think about adjusting a plan if you have a history of bone stress injury, Achilles tendinopathy, recent injury, poor sleep, or limited training time.

The goal is not to throw away your generic plan. It is to stop following it blindly and start making it fit the runner in front of it.

In this episode, you’ll learn:

• Why individualised programs often outperform generic ones
• Why generic running plans can still be useful
• How to adjust your expectations when using a pre-set plan
• What to change if you have a history of bone stress injury
• How to modify speed, hills, and sprint sessions with Achilles tendinopathy
• Why strength and rehab work need to be prioritised
• How to choose the most important sessions when time is limited

You have downloaded a marathon, half marathon, or triathlon training plan. It tells you to run in Zone 1, Zone 2, Zone 3, or maybe gives you interval intensities… but how do you actually know what those paces are for you?

In this episode, I explain how to take a generic training plan and make it more specific by applying your own training paces. We go through two practical methods you can use without a lab: the talk test and a simple 1-mile / 2-mile critical speed test.

DOWNLOAD THE FREE CRITICAL SPEED CALCULATOR HERE:

https://www.thedistancedr.com/criticalspeedcalculator

I explain how the talk test can help you identify easy running, moderate or threshold-type work, and harder efforts, and why critical speed can be a useful anchor for setting more objective training intensities. I also cover why generic heart-rate formulas and old race PBs can sometimes lead you astray.

This is a practical episode for runners and triathletes who want to stop guessing, train with more confidence, and make their plan actually fit the athlete in front of it.

In this episode, you’ll learn:

• How to apply your own paces to a generic training plan
• How to use the talk test to guide training intensity
• What critical speed is and why it can be useful
• How to test using a 1-mile and 2-mile effort
• Why “220 minus age” is not a great way to set heart-rate zones
• Why your current fitness matters more than your old PBs

If you are a runner, triathlete, or endurance athlete who has ever walked into the gym and thought, how much weight am I actually supposed to lift? this episode is for you.

In endurance sport, we usually have clear intensity markers like pace, power, heart rate and cadence. In the gym, it often feels much less obvious. In this episode, I break down the 3 main ways to measure strength training intensity: percentage of repetition maximum, RPE, and reps in reserve.

I explain what each method means, where each one can be useful, and why I generally prefer reps in reserve for endurance athletes. We also cover how to apply these methods to heavy strength work versus muscular endurance work, why gym intensity often gets confused with cardio effort, and the common mistakes that can leave endurance athletes underloading their strength training.

If you want your gym work to actually transfer to performance, durability and meaningful adaptation, this episode will help you stop guessing your loads and start training with more intent.

If you’ve been told to stop running because of injury, illness, travel, surgery, or just life being life, your first instinct is usually, “I don’t want to lose my fitness.”

That makes sense. But fitness is only one part of what makes you feel good when you run.

In this episode, I unpack the four key ingredients that help you still feel like a runner when you return:

• aerobic fitness
• strength
• tendon stiffness and elastic energy return
• tissue tolerance to running loads

We cover why cross-training can maintain fitness but still leave you feeling flat, clunky, and heavy when you get back to running, and what to focus on instead so your return feels smoother, stronger, and more springy.

If you’re in a phase where you can’t run right now, this episode will help you think differently about what to train and why.