Answers

Why am I so tired in my 40s?

Short answer

Poor sleep quality, burnout, dehydration and heavily processed foods can all leave you feeling tired in your 40s. Low iron or vitamin D can also contribute. Lots of cardio without enough food can stress your body and make it conserve energy. Better sleep, whole foods and regular walks may help improve your energy.

By Dai Manuel, CrossFit L2, HYROX L2, Precision Nutrition, NeuroChange Practitioner. Last reviewed 26 September 2026.

Who this is for

For dads in their 40s who feel worn out and want a practical starting point. This is coaching and archive context, not diagnosis or medical advice; take concerning fatigue or decisions about testing and supplements to a qualified healthcare professional.

Why am I so tired in my 40s?

Poor sleep quality, burnout, dehydration and heavily processed foods can all contribute to feeling tired in your 40s. Low iron or vitamin D can also play a part. Start with those possibilities rather than treating your age as the whole explanation.

Look at sleep quality, not just time in bed. Also notice whether work or activities you used to enjoy now feel heavy. The archive describes that shift as a possible sign of burnout, not a diagnosis.

Could my workouts be draining me?

Yes, especially if you are piling on cardio without eating enough. The archive describes that combination as a cycle: lots of movement adds stress, too little food leaves insufficient energy coming in, and your body compensates by conserving energy.

The practical takeaway is not to push harder automatically. Look at your training and food together. More cardio and less food are not always the answer.

What can I do to support my energy?

Keep the starting point simple: better sleep, whole foods, hydration and regular walks. Choose foods such as fruit, vegetables and lean proteins instead of leaning heavily on processed foods. Getting outside for a walk may also help with stress.

These are coaching steps, not a diagnosis or medical treatment. If your fatigue concerns you, speak with a qualified healthcare professional. Discuss possible low iron or vitamin D and any testing or supplement decisions with them.

Common questions

Can poor sleep quality leave me tired even if I spend enough time in bed?
Poor sleep quality can contribute to fatigue. In the archive, the discussion looks at how restorative sleep feels, not just the hours spent in bed.
Should I do more cardio to boost my energy?
Not automatically. Regular walks may help, but lots of cardio without enough food can stress your body and make it conserve energy.
Could low iron or vitamin D be contributing?
Yes, low iron or vitamin D can contribute to tiredness. This is coaching and archive context, not diagnosis or medical advice; discuss concerning fatigue and testing or supplement decisions with a qualified healthcare professional.

Sources

  1. Embracing Health After 40: Philip Pape's Guide to Fitness, Food Freedom, and Mindful Living
  2. The Hidden Hormone Destroying Your Health: Why You Need to Understand Cortisol Now!
  3. Revitalize Your Routine: Discover 7 Natural Energy Boosters to Supercharge Your Day

Keep going

Where Dai has talked about this

Episodes (18)

  • Episode · jump to 10:03

    Embracing Health After 40: Philip Pape's Guide to Fitness, Food Freedom, and Mindful Living

    And when you combine those two lots and lots of movement, which is stressful in your body, with not enough energy coming in it's a vicious cycle that feeds on itself because your body will compensate. People don't understand. The more you try to run and burn yourself out with this cardio and you're not eating enough, the more the body says oh, I got to shut down and survive, I've got to preserve those calories, and you burn fewer and fewer calories. And then you wonder why you can't lose weight. Eating 800 calories a day and running two hours a day, right, so the less is more is really important. I've had female clients come to me like that. Their hormones are out of whack, they're on thyroid medication and all we do is we say let's drop everything. Let's drop everything. We're going to train maybe three days a week. We're going to lift heavy.
  • Episode · jump to 13:56

    The Hidden Hormone Destroying Your Health: Why You Need to Understand Cortisol Now!

    I mean, I was lucky if I was getting five hours at night. But of the five hours, how much of that was quality? Not very much, because my HRV was tanking and also I just had this overwhelming feeling of being burnt out. Some of the signs of your burnt out. Let's just say you've got a job or a career or a project or something that you're absolutely passionate about. All of a sudden you stop loving it. All of a sudden you're like I don't want to do that or oh my God. That's usually a sign that there's something going on and you may be a few degrees away from full on burnout, when the things that you love that used to bring you a lot of joy in life all of a sudden start to become mature and heavy, start to look at what's going on internally because there might be something off.
  • Episode · jump to 1:41

    Revitalize Your Routine: Discover 7 Natural Energy Boosters to Supercharge Your Day

    That's because heavy processed foods are energy zappers. Opt for whole foods like fruits, veggies, lean proteins and watch your energy soar. A study in the American Journal of Clinical Nutrition shows that high fiber, nutrient rich foods can lead to better energy management throughout the day. It's like putting premium fuel in your car, but we're putting it in our belly. Number three hydration nation people, Water, water and more water. Dehydration is a sneaky energy theme. Even mild dehydration can cause fatigue, as found in a study by the Journal of Nutrition. Think of water as your personal energy drink, minus the sugar crash. Number four move it to improve it. A brisk walk or a quick workout can do wonders. The Journal of Sport and Health Science found that regular physical activity improves energy levels. It's like cranking up your favorite jam.
  • Episode · jump to 0:07

    Revitalize Your Routine: Discover 7 Natural Energy Boosters to Supercharge Your Day

    Hey energy seekers and vitality enthusiasts, Welcome back to another Fit Tip Friday here on the 2% Solution Podcast. I'm Dai Manuel, your host and energy booster, here to zap some life back into your day. Today we're diving into a question many of us ask ourselves why am I experiencing a decline in energy levels and how can I boost my energy Naturally? So let's unravel this mystery with some fun, engaging and super useful info. So you ready to power up? Let's do this. First off, let's talk about why our energy might be on a downhill slalom. Did you know? According to a study published in the Journal of Clinical Sleep Medicine, poor sleep quality is a major culprit. It's like trying to drive a car with flat tires. Not much fun, right? Just ask my friend Bob. He used to drink coffee like it was water, but still felt like a sloth.
  • Episode · jump to 12:30

    Embracing Health After 40: Philip Pape's Guide to Fitness, Food Freedom, and Mindful Living

    But also, as we age, it doesn't mean it's a real instant verdict that we can't get healthier than we were in our 20s, as an example, you know. So please speak to that. I'd love to hear your thoughts. Yeah, it is a mindset thing, and where my engineer hat comes in, and you know I- call myself a physique engineer. I love it. Is if we can create massive awareness of what choices we are making that lead to these feelings, that lead to our training and our eating and our diet and thinking that we don't have enough time in our schedule and whatever else. Rather than try to unravel the psychology, which is very difficult and I'm not a psychologist either I'd rather say why don't we just measure or track to measure the things we want to measure? What do we want to measure? We want to measure what's going in our mouth of how it makes us feel.
  • Episode · jump to 16:37

    The Hidden Hormone Destroying Your Health: Why You Need to Understand Cortisol Now!

    Incorporate stress-reducing activities into your routine. Take breaks during work. Practice deep breathing exercises. Spend some more time doing the things you love. Second to that mindfulness and relaxation techniques. These are simple. They're accessible. They don't cost anything. Mindfulness and relaxation techniques are powerful. Whether it's meditation, tai Chi, maybe just going for a walk outside. These practices can significantly reduce stress and start to balance and harmonize your cortisol levels. The American Mindfulness Research Association has found that mindfulness practices are highly effective. These are just a few things. There are a few things that don't take a lot of energy to go out and do, but what it can pay you back as far as dividends is immense. I mean, it's life-changing. So what's holding you back? Just start doing it right. Get out there for a walk.
  • Episode · jump to 3:08

    Revitalize Your Routine: Discover 7 Natural Energy Boosters to Supercharge Your Day

    No joke, laughter is a fantastic energy booster. It releases positive endorphins, which are your brain's feel good neurotransmitters. A good chuckle can light up your energy like a literal Christmas tree. Next, you gotta get your vitamin D. It's literally sunshine in a bottle. It's an nature's energy drink, because a lack of vitamin D, which we get from the sun, can lead to fatigue, Especially this time of year. Right, I live in Vancouver, Canada. I mean hello, gray skies, Wet, cold weather, Shorter daytime. I load up on vitamin D3 this time of year and it makes a big difference. So step outside, soak in some rays and let the sun charge you up like a solar panel. And when you don't get the sun, some vitamin D3 supplementation does wonders. Lastly, check your iron levels. Low iron equals low energy. Iron is crucial for transporting oxygen in your blood.
  • Episode · jump to 8:01

    Overcoming Low Testosterone Naturally: My Journey from Feeling 84 at 34 to Optimal Health

    Here are eight natural ways to keep your tea in tip top shape. And, trust me, they're easier than folding a fitted bed sheet. And those guys out there, you know what I'm talking about. Kristi, my wife can test to this my efforts. When I get that out of the dryer, I roll it up into a tight ball and I just throw it in the top of the closet. I don't even try to fold those fidget sheets in where I just don't know how. So I refuse to invest any time in it. But no, testosterone is not just a buzzword from fitness mags. It's literally a crucial hormone for men's health, and as we age, our tea levels tend to take a bit of a dive. But don't worry, there are natural, scientifically backed ways to help maintain those levels, number one being embrace quality sleep. Let's talk about sleep. It's more than just closing your eyes. It's about quality rest.

Articles (11)

  • Article · Why you're tired all the time after 40

    Why you're tired all the time after 40

    Most men who tell me they are exhausted are not sleep deprived. They are running a stress response that never gets switched off, and the body has quietly downgraded them to save power. FIG. 01 The part nobody photographs. I have had this conversation with more men than I can count. It usually arrives about ten minutes into a first call, in roughly the same words. I'm not unhealthy. I'm just tired. All the time. Then comes the list of things they have already tried. Going to bed earlier. Cutting coffee after noon. A sleep tracker. A blood panel their doctor called unremarkable. Sometimes a second panel, from a private clinic, because the first one felt like it missed something. Here is what I have learned from twenty years on my side of that call. Most of these men are not sleep deprived in the way they think.
  • Article · What energy-saving mode actually means

    Why you're tired all the time after 40

    Your body cannot tell the difference between a predator and an unread email from your boss, so it holds the allocation system open and keeps making the same trade. Energy now, maintenance later. Run that for a decade and later arrives. That is the fatigue. It is the interest payment on ten years of borrowed energy. Gallup's most recent global workplace data puts 40 percent of employees experiencing a lot of stress on any given day, with only 20 percent engaged in their work. Those two numbers together describe a very specific exhaustion: high activation, low meaning. It is the most draining combination there is, and it is the water most of the men I coach have been swimming in since their early thirties. Nobody arrives at a coaching call saying they have chronic autonomic overactivation. They arrive with a pile of separate small complaints they have never connected.
  • Article · Common questions

    Why you're tired all the time after 40

    Your body is telling you the allocation is wrong. You are one decision away from changing the allocation. Not from fixing everything. Just from changing the allocation. Why am I tired all the time even though I sleep enough? Because sleep quantity is only one input. If you are genuinely getting seven or eight hours and still wake up flattened, the likely cause is a stress response that never switches off, which spends energy on threat readiness instead of repair. More sleep does not fix an allocation problem. Can stress make you tired all the time? Yes. Chronic activation keeps the body prioritising immediate threat response over digestion, repair and recovery. Over years that produces persistent fatigue that does not respond to extra sleep. What blood tests should I ask for if I am always tired?
  • Article · Introduction: Cultivating Health and Happiness... A Whole Life Approach

    The Whole Life Fitness Manifesto

    The book goes deeper. This page is the version I still hand to men on a first call, because it fits in their life today. The 2% Solution. Play it here, with the full transcript on the page. The earliest written record of the two percent framework. The least exercise that actually does something, and the part everyone leaves out. Most men over forty who feel exhausted are not sleep deprived. What is actually going on.
  • Article · One year of putting my mental health first

    One year of putting my mental health first

    One early morning in July I locked eyes with my reflection while shaving. The eyes looking back at me were faint. I was 44 and feeling 64. Originally published on LinkedIn on 18 July 2022 and republished here with light editing only. The sixty days it describes became MERGE60 . FIG. 01 July 2021. Day one of the sixty that became MERGE60. How much can change in a day? A week? A year? How about a lifetime? Well, it has been one year of following my MERGE60 lifestyle, and I am happy to say things keep getting better and better. Have you noticed how people describe getting older as synonymous with the body slowing down while enduring the day-to-day suffering from aches and pains? They make it seem like falling apart as you age is normal. As I entered my 45th lap around the sun in 2021, I wondered why we just blindly accept this version of aging and all that comes with it.
  • Article · Functional training for optimal health

    Quality of life far outweighs quantity of life

    The adage use it or lose it rings all the truer as we age. Start implementing functional fitness into your lifestyle today to ensure a capable, pain-free future. Written in 2017, and it is the earliest piece in this archive that argues for healthspan over lifespan. That argument is now the whole premise of the coaching. The specific home programs named in the original have been left out because two of them no longer exist. The 2% Solution. Play it here, with the full transcript on the page. Most men over forty who feel exhausted are not sleep deprived. What is actually going on. What held up from my 2016 column, and the part I oversold. The real timeline, and every number from a sixty-day cohort of twenty-three men.
  • Article · Why is the idea of exercise so intimidating?

    No longer fat, sick and nearly dead

    To go from feeling that you do not have the energy to start moving, even a little, to hitting the gym or working with a personal trainer is a huge shift. Who has not thought, I am too exhausted after my commute to work out, or, once I have put the kids into bed I am exhausted, or, I cannot work out because I cannot afford a gym membership? I know that 7 years ago I suffered a bad bout of Excusitis, an intolerable disease preventing one from doing anything productive, or more commonly known as I-will-do-it-tomorrow-itis. I had a lot of excuses, also known as bad habits, running through my head daily. What made me feel worse, here I was a fitness professional and I was earning an income helping people overcome their excuses to get back on a path of optimized health.
  • Article · Quality of life far outweighs quantity of life

    Quality of life far outweighs quantity of life

    People are obsessed with living forever. Meanwhile we are getting more ailments from poor fitness and lost mobility as we age. Originally published on LinkedIn on 2 February 2017, itself republishing an article written for Fresh Magazine, and reproduced here with light editing only. FIG. 01 FIG. 01 / Use it or lose it, and the losing is quiet. Generally speaking, I seem to be reading more and more about longevity these days. It would seem that people are obsessed with the idea of living forever. And granted, medical science is doing a wonderful job of allowing us to live longer and longer. However, as a whole, we are also experiencing more and more ailments as a result of decrepitude, poor physical fitness and lack of mobility as we age. It is about time for an intervention and a call to help people get back to basics. Envision this.

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