If you’ve ever felt that deep, nagging ache in the back of your heel, the one that’s stiff and sore for the first few steps out of bed and then warms up once you get going, you’ve met tendinopathy. And if your instinct was to stop, rest it, and wait for it to heal, I understand why. It’s also the single most common mistake I see athletes make.
I have worked through tendinopathy myself and completely resting it, will do NOTHING to heal a tendon. Careful and progressive loading is what the tendon actually needs to rebuild. Here’s why, and how to think about it.
Rest Feels Right. It Also Doesn’t Work.
A muscle strain and a cranky tendon are different problems. When you rest a tendon completely, it doesn’t come back stronger. It gets less capable. The tendon loses the very capacity you need to run pain-free, so when you return to training, the same loads that irritated it before now land on a weaker structure. You feel better for two weeks off, then you’re right back where you started within days of running again. Sound familiar?
Tendons are living tissue that adapts to the demands you place on them. Take the demand away entirely and they detune. The fix for an under-capacity tendon isn’t less load. It’s the right load, applied in the right order.
How Load Actually Repairs a Tendon
Tendons respond to mechanical loading by remodeling. When you load a tendon in a controlled, progressive way, you stimulate the cells inside it to reorganize and build, gradually increasing the tendon’s stiffness and its ability to store and return energy. Over weeks and months, that’s what raises your pain threshold and your performance ceiling at the same time.
The keyword is progressive. You’re not trying to blast the tendon or push through sharp pain. You’re giving it a reason to adapt, then a slightly bigger reason, then a bigger one, staying just ahead of where it is without overwhelming it. Think of it the way you’d build mileage: you don’t jump from 20 to 50 miles a week, and you don’t fix a tendon by going from zero to plyometrics.
The Loading Ladder
Rehab research generally moves a tendon through stages, from least demanding to most. You climb the ladder as pain and capacity allow.
Rung one: isometrics. These are holds. You contract the muscle and load the tendon without any movement at the joint, like rising onto your toes and holding, or pushing against something that doesn’t move. This is the smart on-ramp when a tendon is irritable, because you can load it meaningfully without the stretch-and-shorten cycle that tends to aggravate it early on. You get to start building capacity right away instead of waiting.
Rung two: heavy slow resistance. Once you tolerate holds, you progress to slow, heavy, full-range strength work, calf raises through their full range with real load, moving slowly up and down. This is where a lot of the meaningful tendon remodeling happens, and the evidence base here is strong.
Rung three: energy storage and release. The final rungs reintroduce speed and spring, hops, bounding, and eventually the running-specific loads your sport demands. This is where the tendon relearns to act like the spring it’s supposed to be. You don’t get here first. You earn it.
A Straight Answer About Isometrics
Isometrics got popular a few years ago on the back of a widely shared finding: a 2015 study of athletes with patellar (knee) tendon pain found that isometric holds produced a large, immediate drop in pain.1 That’s a real result, and it’s why you’ll hear coaches talk about isometrics as a pain-relief tool you can use even in-season.
But here’s the honest part, and it matters because so many of you are dealing with the Achilles specifically. When researchers tested that same immediate pain-relief effect in people with mid-portion Achilles tendinopathy, they didn’t find it. In a trial of 91 patients, isometric calf holds produced no meaningful immediate pain relief compared to other approaches, or even to rest.2 The dramatic painkiller effect that made isometrics famous shows up more reliably in the patellar tendon than in the Achilles.
So don’t do your isometric holds expecting the ache to vanish on the spot. That’s not why they’re on the ladder. They’re there because they let you start loading a grumpy tendon safely and begin rebuilding capacity from day one. The pain relief, when it comes, comes from the weeks of progressive loading that follow, not from a magic hold.
That distinction is the whole point of doing this honestly. Isometrics are the on-ramp, not the destination.
Let the Tendon Tell You Where You Are
The reason I don’t hand athletes a rigid day-by-day tendon protocol is that tendons don’t read calendars. They respond to load, and the tendon itself gives you the feedback you need if you’re paying attention. Two rules I coach:
Use a pain scale, and stay in the acceptable range. Some discomfort during loading is okay for a tendon; sharp or climbing pain is not. A common guideline is to keep pain at a low, tolerable level during and right after the work, not pushing into the range where you’re wincing.
Judge by the next morning. The real test isn’t how it feels during the exercise, it’s how the tendon responds over the next 24 hours. If it’s calmer or the same the next morning, the load was appropriate. If it’s noticeably more irritated and stiff, you asked for too much, and you scale back the next session. That morning check-in is your traffic light: green to progress, yellow to hold steady, red to back off.
This is exactly how I’m managing my own Achilles. I’ve been using an AlterG anti-gravity treadmill to control the load precisely, dialing body weight up as the tendon earns it, and reading that next-morning response to decide each day’s dose rather than forcing a predetermined plan. Progressive, responsive, patient. That’s the game.
The Bottom Line
Your sore tendon isn’t asking you to stop. It’s asking you to load it intelligently: start with holds to get on the ramp, build through heavy slow strength, and earn your way back to speed, all while letting the tendon’s day-to-day response set your pace.
Rest might quiet the pain for a week. Load is what rebuilds the tendon. Respect the difference, climb the ladder in order, and you come back not just healed, but harder to break next time.
Dealing with a nagging Achilles or a cranky tendon and not sure how to load it? That’s exactly the kind of thing our coaching is built for. Reach out and let’s build you a plan that fits where your tendon actually is.
This article is educational and reflects current research on tendon rehabilitation; it isn’t a substitute for individualized assessment. If you have persistent or worsening tendon pain, get evaluated by a physical therapist or sports medicine professional.
By Tom Clifford | Without Limits
Let’s start with something you probably didn’t expect to read on a coaching website: I used AI to help write this blog post.
I know. Stay with me.
Because here’s the thing, AI is genuinely useful. It can research, organize, draft, and produce content faster than any human. I’m not here to tell you technology is bad. I coach athletes for a living. I know that tools matter.
But there’s a difference between a tool and a coach. And right now, a lot of runners and triathletes are confusing the two, and paying for it on race day.
The App Told Me to Run 8 Miles. So I Did.
Your AI training plan doesn’t know that your left knee has been talking to you for three weeks. It doesn’t know you had a terrible night’s sleep because your kid was sick. It doesn’t know the humidity hit 90% this morning and your “easy 8 miles” just became a survival march.
It just said 8 miles. So you ran 8 miles. And now your knee is angry.
I’ve been running for 32 years. I’ve seen this pattern hundreds of times. The athlete who follows the plan perfectly, and breaks down because the plan didn’t know them.
An algorithm can build a plan. It cannot read your face when you show up to group training at 5:30am looking like you haven’t slept in three days. I can. And I will absolutely modify your morning around that, because I know the difference between an athlete who needs to be pushed and an athlete who needs to be managed.
That’s not something a language model learns from your heart rate data.
What 32 Years in the Sport Gives You
I ran my first race in 1993. I’ve trained through heat, snow, woke up at 5am in 2 degree temps, hurricanes, injuries, bad seasons, great seasons, and one memorable 50K.
In those 32 years, I’ve learned things that don’t exist in any database. I know what a runner looks like when they’re about to hit a wall three miles before they think they will. I know when an athlete says “I feel fine” and means it, versus when they say “I feel fine” and are lying to themselves. I know which athletes train great alone but fall apart in race environments — and how to fix that.
You cannot compress 32 years of real experience into a training plan prompt. You can’t ask ChatGPT “what does a runner look like six weeks before they quit?” and get an answer that’s worth anything.
Experience isn’t data. It’s pattern recognition built from being there, in person, in conditions, in the real world — over and over and over again.
The Group Is the Secret Weapon
Here’s what no app is giving you: the energy of 30-60 people showing up at 5:30am.
When you train alone with a plan on your phone, motivation is entirely on you. Some days that works. Most days, if we’re being honest, it doesn’t. You negotiate with yourself. You shorten the run. You skip the tempo intervals.
In a group, something different happens. The person next to you is going. So you go. The pace picks up. You find something you didn’t know you had. You finish a workout you would have quit at mile 2 if you were alone on a treadmill.
That dynamic is not replicated by any app, any algorithm, or any AI. It is a human thing. It requires human beings in the same space, at the same time, suffering and succeeding together.
Motivation delivered through a push notification is not motivation. Motivation is your training partner refusing to let you slow down with 400 meters left.
I’ve watched athletes nail every workout in their training plan and then fall completely apart in a real race environment. You want to know why?
Because they trained in a controlled environment and expected race day to be controlled.
It isn’t.
Race day is humidity and headwinds and a porta-potty line that cost you four minutes and a nutrition strategy that stopped working at mile 9. Race day is the athlete who goes out too fast in the first mile and blows up by mile 6, because no one ever taught them what controlled effort actually feels like in a crowded race start.
When I coach athletes onsite, I teach them to train in the real world, in real conditions, with real obstacles, with real people around them. We run the hills that hurt. We do brick workouts in heat when it would be easier to reschedule. We practice start-line strategy because the start line is where bad decisions are made most often.
A training plan tells you what to do. A coach teaches you how.
The Collaboration Nobody Talks About
Here’s the part that gets left out of every “AI vs. human” conversation:
The best coaching relationships are collaborations.
When I build a plan for an athlete, I’m not handing down commandments. I’m starting a conversation. How did that feel? What’s your body telling you? What happened at work this week? Are we being realistic about this timeline?
That back-and-forth, the athlete’s honest self-reporting, my experience interpreting it, and the ongoing adjustment of the plan, that is where results come from. Not from the plan itself. From the process of building it together, in real time, with a human being who gives a damn whether you make it to the finish line.
So Where Does AI Fit?
I’ll be straight with you: I use AI tools to make my coaching better. I use them to organize, to research, to communicate faster with athletes, to help produce content like this. Technology makes me more efficient.
But efficiency is not coaching. Efficiency is infrastructure.
The coaching is me, on the track at 5:30am, watching how you’re moving, adjusting your effort, pushing you past what you thought was your limit, and celebrating with you when you cross a finish line you weren’t sure you could reach.
Thirty-two years of that. No app included.
The Bottom Line
Use the apps. Track your data. Listen to the podcasts. Read the blogs. I’m not against any of it.
But if you’re serious about your running or triathlon, if you have a real goal and a real timeline and you actually want to get there, hire a coach. A real one. One who’s been where you are, has seen what you’re going through, and will be standing there at the track when the plan says easy day but your body says otherwise.
Success in endurance sports doesn’t come from the perfect algorithm. It comes from collaboration between an athlete who shows up and a coach who knows what to do with them when they do.
The work is still the work.
Do the work.
— Tom
Tom Clifford is the CEO of Without Limits Endurance and a USATF Level 2 and USA Triathlon certified coach with 32 years of running experience. He coaches runners and triathletes of all levels across the Carolinas — in person, in groups, in the real world.
Ready to stop training alone? Learn more about coaching programs at Without Limits.
Have you noticed feeling fatigue, tired or heavy legs during running, difficulty completing workouts, or not recovering well before the next session?
You may have low iron stores (as measured by low serum ferritin). In fact, many athletes experience some form of nutrition related fatigue that is related to one of the following:
- Under fueling in general, not eating enough energy (calories) to support training.
- Not taking in enough carbohydrate during the time just before, during or after training.
- Eating inadequate iron to support the demands of running and suffering from lower production of hemoglobin and red blood cells – that carry oxygen to working muscles.
Low levels of hemoglobin in the blood, or low levels of the iron storage protein ferritin, can have a profoundly negative impact on your ability to have successful workouts and races.
Low ferritin levels can cause poor performance, even when hemoglobin levels are normal.
Research with high school cross country runners has shown about 3% of boys and 40% of girls were iron deficient at the beginning of the season and even higher numbers were seen by the end of the season.
There are 3 primary sons for why female runners are at greater risk for iron deficiency:
- dietary intake of iron tends to be very poor.
- menstrual cycles cause a substantial loss of blood. This increases the body’s demand for iron.
- running training itself causes an additional loss of iron – this happens primarily through gastrointestinal blood loss.
Distance runners can suffer from impaired performance even at iron levels at the low end of the “normal” reference range. (12 – 200 ng/ml for women; 12 – 500 ng/ml for men)
Athletes with ferritin levels at the low end of “normal” for the general population were found by researchers to exhibit many of the same symptoms as athletes with clinically low iron (<12 ng/mL).
Runners should aim for ferritin levels above 40 ng/mL to avoid fatigue and impaired performance from iron deficiency.
The best and easiest way to fix iron deficiency is the most obvious one: increase the iron sources you consume. This can involve increasing your dietary intake, taking an iron supplement, or, preferably, both.
Meat, especially red meat is rich in heme-iron, the form of iron that is readily absorbed and least impacted by factors that impair the absorption of non-heme iron (found in grains, beans, and vegetables). In fact, eating varied meals that contain both heme- and non-heme iron improves absorption of the plant-based sources. Meat, poultry and fish all share this ability to improve absorption of non-heme iron foods.
There is a significant benefit of iron supplementation in iron deficient athletes, both when it comes to increasing serum ferritin levels and to increasing aerobic performance.
Runners Essentials Daily Vitamin Formula by Without Limits is designed to support the endurance athlete’s needs for key nutrients including iron. The form – Ferrous Fumarate is less likely to cause GI problems (constipation), and the dosage – 22 mg (or 122% of Daily Value) is intended to prevent diminishing iron stores. It is recommended that you take the 2 capsules with a Vitamin C rich juice to increase absorption, apart from meals, antiacids, tea, or Calcium supplements which can inhibit iron availability for absorption, or at bedtime for better GI tolerance.
We all go through challenges, and after 16 years in business I hit a major challenge with
Without Limits. REBRANDING! Running a business
is a journey of ups and downs.
Without Limits turned out to be my career, which I never would have predicted a long time ago. It turned out to be better than expected and I thank God for giving me that blessing.
So why did we rebrand? I could say it was time for a change, and maybe it was, but unfortunately a much bigger athletic company than mine thought our brand looked too much like theirs and change was inevitable.
The decision was easy, don’t fight this, instead, make things better!
We are who we are, and we don’t want anyone else to think we are trying to be them. So for all of my friends and followers, WOL is Without Limits and that is what it was called from the start.
Our journey continues and our story gets better and stronger. We want to thank all of our athletes and the folks that support our events and wear our gear! Our mission continues to set goals and break through our old limits. Limits are not always defined by speed. While getting faster and improving performance is a part of endurance sports, so is mental improvement and overcoming obstacles in sport and in life. All this trickles down to our inner core of improving the SELF. WOL is what people have called Without Limits since we started. There is no symbol to define without limits than the words and letters themselves!
Embrace the Challenge and continue to LIVE WITHOUT LIMITS!
A big thanks to our athletes, coaches, colleagues, friends , and most importantly my wife
Annette Clifford! She took over the administration and helped me tremendously when we first got married in 2011. She gave up her job with a big unknown. We developed a brand together have some amazing people around us!
Cheers to the future and thank you for your support!
The Journey to Without Limits
by Kim Baldwin
January 2022
September 2015. I was lying in an ICU bed thinking to myself, how the F*ck did I get here?
Six months before that, I had started a slow descent into a darkness I had never known. I was close to weighing 300lbs. And I was training for the SMART Ride, a 160-mile bike ride from Miami to Key West, in November. When I began to experience chest pain and shortness of breath, I told myself it was due to my weight and to shut up. This is what being 300 lbs. means. For months, it was nothing but me, my bike and the horrible stories I told myself. My daily practice was punishment through starvation, mileage, self-bullying. Rinse. Repeat.
By mid-September, I just not feeling well. So what did I do? Compete in the Wrightsville Beach Triathlon, just as I always had. My thinking was, well, you are getting a cold, you really don’t eat, you weigh a lot. This is what happens. Shut up. Continue with the punishment.
That September race day, I entered the water, found my spot, and took off when then gun fired. All very normal. I made it about 10 strokes into Banks Channel. Out of nowhere, I felt a wave of nausea tear through my body, from the bottoms of my feet up. Then I couldn’t breathe. I remember thinking, “I’m gonna be one of those triathletes who dies in the swim and everyone will say, ‘At least she died doing what she loved.” The ironic thing? I did all the swimming, biking and running not from a place of love (or mild enjoyment) but from a place of pure, unadulterated 
punishment.
My hand shot up. The lifeguards raced over, got me on the coast guard boat and took me immediately to the docks at Sea Path Marina where the paramedics were waiting for me. I knew something wasn’t right but when they checked me out, my vitals were ok. They let me go. In my mind, I convinced myself, again, that this is what happens when you are completely out of control with your weight; never mind I had done that swim hundreds of times with no issues.
Two days later, I ended up in the ICU. Both lungs were filled with blood clots and I had what they call a saddle pulmonary embolism. (This is not something you want to Google.) When the doctor came in my room his jaw hit the floor. He couldn’t believe I was alive. People don’t live through what I experienced. I wasn’t supposed to be here.
While taking months off from work and going to pulmonary rehab, I got much needed time to think. I knew I couldn’t ruin the do-over I had been gifted. I couldn’t spend the next half of my life living in darkness, anger, shame and blame.
For the next three years, I dug deep. I did the work. I unraveled my childhood trauma and started to see how that impacted every single strand of my life, especially my relationships with food and exercise. With the help of a nutritionist specialized in eating disorders and a therapist specializing in childhood trauma, I slowly started coming out of the darkness. I started to understand the stories I told myself were just that, stories.
I learned my eating disorder probably started when I was about five or six years old. I uncovered the root of my depression, anger, shame and toxic thinking. And I finally understood how it all was inextricably linked. I starved myself as a form of punishment. I exercised as punishment. Food brought me no joy. In fact it brought me the exact opposite. Who eats for pleasure? Running is fun?
In the movie “28 Days,” one of the characters, upon leaving treatment, wants to adopt a dog. His therapist says he can have a dog if he takes care of a house plant for a year. If the plant doesn’t die, he can get a dog.
That’s what my three years of doing the work was for me. I lost 100 lbs., got my mind right, and felt stable enough – mentally, physically, spiritually – to start exercising again. I wanted to see what a body with 100 lbs. less could do.
I joined Without Limits (WOL) and started with swim practice twice a week. Then I added run practice twice a week, signed up for Training Peaks and all of a sudden, I had a coach and long runs on Saturday.
Intimidated. That’s how I spent the first few months of swim and run practices. I felt so insecure. I was the slowest one. I didn’t want to get in anyone’s way. Did I really belong? Were my old thought pattern and stories creeping back in?
After one particular run practice I left in tears. I didn’t realize anyone noticed. Coach Kristen called me the next morning. She said to me, “Boo, you belong.” Somehow, she knew. That day, it all changed. I needed to get out of my own way. So I did.
Then COVID hit. All of a sudden everything was shut down. Even swimming at Wrightsville Beach was shut down. The gift of COVID was that I realized just how important running and swimming were to my mental and physical health. I needed movement. It was my way out of the darkness. It relieved my anxiety. It allowed me to properly fuel my body. Talk about a 180!
There was another COVID gift. I realized just how important WOL was to me in other ways. The coaches gave me accountability and encouragement. And I made friends too. Amazing friends! Relationships of any kind are almost impossible when you tell yourself stories. So in those first few months of the pandemic, it was like time stood still. I was able to reflect on what I was missing. I saw how important this community of athletes is to me. The friendships I’ve made far outweigh any PR.
Six years later, post-clots, mental breakdown and eating disorder diagnosis, I’ve never been better. Sure, I have my days. We all do. Now, I sit with my feelings, try to understand them, and then move on. Sometimes I work them out on the track or in the pool. Sometimes I groan with the ladies at Starbucks post-workout. The one thing that remains consistent is when I leave practice, my cup is always full.
I couldn’t have imagined me being a member of WOL. But here I am, one of its ardent supporters. My original assignment was to write about why I joined WOL. But honestly, it’s more about why I stay. It has truly been a journey. And one that is nowhere near over.
Healthy Eating Through the Holidays
by Diana Davis RDN, LDN – Without Limits Dietitian Nutritionist
Do you have a plan for your holiday eating?
Yes, I know you want to celebrate the holidays! The parties and celebrating have already
begun, and I want you to be able to eat, drink and be merry, BUT not too much!
You know the drill, too much eating, drinking, and merriment can add up to feeling bloated and
lethargic in the “short run” and too much partying will produce gains in body weight and body
fat (which is never good) in the “long run!” All of this typically equals a few missed workouts at
a minimum and in some cases, a really “good excuse” to take the month of December off from
training!
So, what can you do? Consider having a plan.
- Day of a holiday event/party: get your workout in early; hydrate with lots of water
throughout the day; eat a balanced meal or snack before you go to the party; bring a
vegetable-forward appetizer to share (such as a meat, cheese & veggie tray, a hummus
& veggie tray, or a spinach and artichoke dip with veggies and crackers/chips)
- At the holiday event/party: HAVE A GOOD TIME; continue to drink water – between
rounds of alcohol; make sure to eat with attention to more protein and veggies, and if
your holiday gathering is an all-day event, get outside and get active with the kids!
- Day after the festivities: get back to training as quickly as possible – you will never regret
it; resume your regularly scheduled eating; and always water first, veggies most!
Interested in starting the New Year with a nutrition plan customized for your personal goals?, I
would love to be your nutritionist! I am licensed to provide nutrition counseling in both NC and
SC and am an in-network provider with several major insurance carriers. Reach out to me by
email dianadavisrd@gmail.com or through the Without Limits app or website
https://www.iamwithoutlimits.com/membership/nutrition
