§1 – Introduction

(Part 1 of 8 in ~ Changes and Results)

I’ve lost a lot of weight and gotten a lot stronger in the last few years. But how, exactly, did I get to where I am now?

In 2011, I didn’t like where I was, and I don’t mean, “I was embarrassed about being fat.” I mean I was physically uncomfortable being sweaty, physically unable to get comfortable sitting, grumpy all the time, tired all the time, and more. I really wanted to change and I knew I needed to change before the Doctor started one of those, “Let’s talk about these numbers,” conversations.

Around that same time I’d discovered a few blogs…

I’d read a lot over at Nerd Fitness. I read all of Steve Kamb’s inspirational and motivational stuff.

The big take-away from NF was the loud-and-clear message about what does NOT work: Simply getting a gym membership does not work, declaring a New Year’s resolution does not work, and generally trying to “turn over a new leaf” does not work. Fortunately, rather than come away hopeless, I took it as a big comforting confirmation that I am not alone in sucking at changes.

Whatever it is that I’d been doing, that is EXACTLY what was NOT working.

I also read everything from Leo Babauta over at Zen Habits. For example, When Willpower is Trumped By Bad Habits is a great example of Leo-zen. Eventually, I finally teased a few more threads out of the Gordian knot that was my problem:

I am weak in willpower.

I need to stop beating myself up about failures and shortcomings.

I began by slowly making progress on some “health” projects, improving my sleep and more. (I’ll go into all of that in detail in subsequent parts.) As soon as I began taking Parkour classes, it became clear that I needed to ease into actual running. I also concluded that “regular” footwear was going to act as a crutch and slow down my progress in Parkour. (Long story. Just go with it for this discussion.) So I also switched to minimalist shoes for Parkour, for running and daily wear.

The result of running and Parkour? I was stiff, achy and sore literally all the time. It became glaringly obvious that I needed to start doing “recovery work” — stretching, massage, miofascial release, and basic range-of-motion movement if I was to have any hope of keeping up my hard work.

…and on and on.

I built upon each small success, one small step at a time.

Which brings me to today, and this series of posts. Here I’m going to document my journey by spelling out all the things I did. Hopefully, this roadmap will inspire others.

Next up, some Philosophy!

§2 – Philosophy

(Part 2 of 8 in ~ Changes and Results)

I wandered a haphazard path until I learned some philosophical lessons and made some critical, first changes. I tried many different things, keeping what seemed to help and abandoning what did not. It is only through hindsight that I can share the things which are the foundations of my progress.

The first step in my journey was realizing I was unhappy. This realization — detecting it, understanding it, believing it, surrendering to it, and finally owning it — was the first piece of bedrock on which I started building. I was clearly in a slow, downward spiral, and this realization led me to thrash around trying to change things.

( I didn’t find this until years later, but Leo Babauta has a wonderful post about, The Spiral. )

My initial progress was glacial as I began working on the twin skills of self-awareness and self-analysis. Although I began my journey blissfully unaware and ignorant, my problems became increasingly obvious. Owning up to each problem required all my fortitude and courage. Step by step I found the motivation to begin changing my life. It was the discomfort of the status-quo which motivated me to change; Without that discomfort — without the self-awareness which created that discomfort — I would simply have continued my downward spiral.

Along the way, it was also important to realize I was fragile (physically, mentally and emotionally), and that I would need to build up a tremendous, new resilience. Becoming mentally and physically resilient creates a comfort zone. It means that bumps in the road may slow, stop, or even set back my progress. But they will never turn my upward spiral into a downward spiral. In truth, I was well into building up my resilience before I understood what I was doing. But as my understanding caught up, it became possible to work intentionally on resilience.

( One article which helped solidify my understanding was about, Anchoring One’s Resilience in Your Authentic Self. )

Although I remain a work in progress, my success is entirely built on the simple philosophy of continuous self improvement. Unfortunately, it is not at all simple to implement. I tried a litany of changes — small and large, easy and hard, crazy and clever, pointless and miraculous — as I incessantly kept learning, experimenting, and building upon each tiny success and advance. The things which worked for me form the remaining parts of this series.

( It wasn’t until far into my journey that I learned of the Observer, Orient, Decide, Act (OODA) loop. )

Which would boil down to these essentials:

– I owned up to being unhappy.
– I built up my skills of self-awareness and self-assessment.
– I built up my mental and physical resilience.
– I began making continuous self-improvement changes.

§3 – Strategy

(Part 3 of 8 in ~ Changes and Results)

The bulk of this series is about the various major changes I have made. In the big picture sense, it’s just a long list of posts with actionable ideas for you to consider. Unfortunately, accomplishing any of these changes requires you to be able to break old habits and create new ones.

There’s plenty of information available on habit change, so I’m leaving the psychology of habit change out of this series. Instead, I’m going to suggest one activity: Keep a habit journal. I started my habit journal, began by trying to fix my sleep, and slowly began my upward spiral.

For the rest of this series I won’t – I promise! – tell you the back story of how I discovered and explored each change I’ll be describing. Instead, I’ll compress each as much as I can, with as much actionable intel as possible. But for this “Strategy” part of the series, I want to tell you the story of how I discovered and started my habit journal.

This entire “Changes and Results” story begins with me realizing I needed to get more, quality sleep. It was a slow realization, and it sprang from some online articles I had stumbled upon. As I read more, I became curious about my sleep, and found I was often thinking about my sleep and how to improve it.

To make any change, new knowledge is required; What would the change look like? What are healthy sleep cycles, duration and times-of-day? What temperature, light and sound levels are conducive to good sleep? What room details (the bed, the colors, the room layout) and room uses (is the room multi-use or a space where I only sleep) are conducive to good sleep? It turns out that all of that knowledge is out there, and so I dug into it to varying degrees until I felt I had satisfactory answers to some of my questions.

But, all that new knowledge accomplishes nothing.

I had identified a problem, (“get better sleep”,) which gave me new questions. From there, my curiosity led me to new knowledge. At that point, I knew what I wanted to change, but right there is where I had always failed.

Enter, stage left, Benjamin Franklin.

One day, still frustrated and making no progress on improving my sleep, I read an article about Ben Franklin. Franklin had set out to improve himself over the course of several years. He came to the conclusion that there were too many different things to focus on for him to improve himself in one broad effort:

It was about this time I conceived the bold and arduous project of arriving at moral perfection. I wished to live without committing any fault at any time; I would conquer all that either natural inclination, custom, or company might lead me into. As I knew, or thought I knew, what was right and wrong, I did not see why I might not always do the one and avoid the other. But I soon found I had undertaken a task of more difficulty than I had imagined. While my care was employed in guarding against one fault, I was often surprised by another; Habit took the advantage of inattention; Inclination was sometimes too strong for reason.

I had reached the same conclusion, (but, alas, without the same eloquence,) when I was unable to change things by simply desiring them to change. Goals such as: sleep better, be less grumpy, and lose some weight, all failed to materialize.

Franklin went on to create a grid, with a row for each virtue and a column for each day of the week. At the end of each day, he put a mark if he felt he hadn’t lived up to that virtue on that day. The goal was then to have no marks on the grid at the end of the week. Each week he would focus particularly on one virtue (and he cycled through his 13 virtue goals.) He began each week by re-reading a small reminder he’d written about the week’s focus virtue (for example, “Humility: Be not Achilles; Imitate Socrates.”) He would then set about focusing on that virtue during the week. Franklin was working on a list of virtues such as Tranquility or Temperance, but his system works perfectly well for anything.

[O]n the whole, though I never arrived at the perfection I had been so ambitious of obtaining, but fell far short of it, yet I was, by the endeavor, a better and a happier man than I otherwise should have been if I had not attempted it.

Inspired by Franklin, I began my habit journal more than ten years ago. At the beginning of each month I create a table with the dates across the top, and a row for each thing I’d like to work on that month. Initially, I had a small notebook just for these monthly habit journal tables. I started with rows for 6, 7 or 8, hours of sleep and put a corresponding mark for each day. This created a rough graph running across the month. That visual graph really gave me a push: “Yesterday’s mark is 6.5 hours, if I go to bed right now, I can put tomorrow’s mark at 7.” (I’ll go into the details of my sleep changes in the next post.)

Eventually, if something becomes an ingrained habit, I remove it from the grid; If it becomes a problem again, I add it back and work on it again. Sometimes I don’t get around to filling in the table, and the next day, I’m thinking, “Not two days in a row! Fill it in!” Which serves to further reinforce my paying attention to my daily goals.

(When I travel, I usually leave the habit journal behind and track nothing. Generally, I don’t have the time and my schedule is changed, so filling it in or even sticking to the habit plans would be tough. But such trips — little breaks from the habit journal — serve as test runs with the training wheels off. A three-day weekend, for example, gives me a lot to think about when I pick up my habit journal upon returning home to my normal routine.)

The monthly habit journal tables grew in size and complexity as I added and tracked more things, and eventually tracked many things. But there’s no need to start with complexity. Start with columns for the days of the month, and make a row for that one thing you want to work on first. Next month, assess how you did, adjust as necessary, and add a row if you want to work on a second thing.

In the very beginning, I used a small, square-gridded, notebook, but my tables eventually outgrew the page size. Years later, I started journalling and I didn’t want to have both a habit journal and a “regular” journal. So I invested the time to copy all the historical grids into my journal so I’d always be able to refer to them.

So what does this actually look like? Here’s my (recopied) habit journal table from the very first month, December 2006:

…and here is the table from, February 2017:

That’s really all there is to it. These little grids are the framework on which I hang whatever it is I’m trying to change.

§4 – Sleep Prologue

(Part 4 of 8 in ~ Changes and Results)

I’ve been talking about writing a post about sleep for years. But as I started writing, it turned into a huge article. Which makes sense, because fixing my sleep is the single most important healthy change I have ever made.

I realized that if I wanted to get a sufficient, healthy amount of sleep — let’s say around 8 hours — I would be spending ONE THIRD of my life sleeping. That means sleeping vastly outweighs any other activity in my life. I became determined to optimize the time spent sleeping and to ARRANGE MY LIFE AROUND SLEEPING. This was the critical, first step.

Failing to plan is planning to fail

I only know how much sleep works for me. You’ll need to find out for yourself how much sleep you need. This is another spot where the habit journal will really pay off. If you can track when you go to sleep, when you wake, how much sleep you get, and your quality of sleep, then you can make changes as you review each month.

One detail I’ve discovered is that some days I simply need extra sleep. So while I have a consistent plan, some days I’m stumble-down tired a half an hour before I’d normally turn in for the night. In these cases I just go to bed a little early, and with that extra half hour I usually feel terrific the next morning. There’s no feeling to match that of walking up, fully refreshed, a few minutes before the alarm.

I started by considering the time I needed to be at work, and subtracted time working backwards (commute, breakfast, shower, etc.) to determine what time I actually needed to get up. It was basically when my alarm was already set for, but it was good to double-check by consciously figuring this out. From there I just backed up 8 hours and that told me when I needed to go to sleep.

That gave me my very first sleep hack: Get to bed at the appointed time. That would lead to sufficient sleep (sufficient is the first hurdle, quality comes next), and a reset of my life at the start of each day. But it was immediately clear that I would have to change much of my evening habit. Dinner had to be coordinated at a more consistent, earlier time, and I had to break the habit of lounging in front of the TV.

This is all VERY hard to do.

I worked to consistently use my habit journal, and to review each month. Each day that I wasn’t in bed on time, I reminded myself that SLEEP was the most important thing in my life. These days — a decade later — I do deviate from the plan. Usually it’s when I’m traveling, or intentionally out late. But the point is: I HAVE A PLAN. My sleep plan sets me up FOR SUCCESS, rather than having no plan, and sabotaging the rest of my life each day, before I even open my eyes.

Partner Buy-in

Since I share sleeping space, this was the first, serious issue I had to solve.

I found that every night we enacted the following scene: I would get sleepy, and ask her, “What time do you want to go to bed?” The response was usually, “I just need ten minutes to finish this up.” Ten minutes later, it’s role reversal: She’s ready for bed, but I’m busy with something new and it’s my turn to ask for 10 more minutes. We’d then repeat this until 1am when we’d both crash, exhausted, and get yet another terrible night of sleep.

( Sound familiar? Maybe for you it’s roommates, or guests that are around all the time. Whatever. )

Our solution was to set a bed time, and a lights-out time. Everyone goes to bed at bed time. At “lights-out” time, the ready-for-bed person, is permitted to turn off EVERY light in the house (because we sleep in darkness), leaving the other to stumble into bed IN THE DARK — no turning lights on after bed time! This means you have to learn to plan the end of your evening so you can have time for your bedtime routine.

Why bed times? Why lights out rules? Because we realize that we must go to bed on time, so we can wake up on time, having slept well.

Sleep is priority number one.

Next up

A long list of sleep hacking ideas…

§5 – Sleep

(Part 5 of 8 in ~ Changes and Results)

Q: I’ve been entirely preoccupied by a most frightening experience of my own. A couple of hours ago, I realized that my body was no longer functioning properly. I felt weak, I could no longer stand. The life was oozing out of me, I lost consciousness.

Picard: You fell asleep.

sigh Sleep. Sweet. Rejuvenating. Blissful. …when you can get it.


There is a huge amount of information about sleep available on the Internet. Over the years, I’ve collected a wide range of references upon which I’ve based my actions and opinions. I do this for a lot different topics, and I have a companion web site where I collect all the health related information I’ve found. In the case of Sleep, please see Sleep Quality, Light Sensitivity in the Human Brain, and Magnesium and Sleep over on Hilbert’s Library.


I sleep best in complete darkness.

Long ago, I had no idea that light was messing up my sleep quality. Light is everywhere in modern life: it comes from windows, from doorways, from the alarm clock’s LED numerals, from the blinking LEDs on the WiFi router. But, after a lot of reading, and over ten years of experimenting, I’m convinced that light is enemy number one.

Sure there are other things which will wake me, (noise, movement, etc) but light is pervasive. Light is subtle. Light is insidious. Rage! Rage against the light!

So the goal for me is complete darkness.

Aside: Yes, I’ve considered using a sleep mask to cover my eyes. However, the human brain is broadly sensitive to light, so I’m not convinced a light mask is as good as a good old-fashioned dark room. See Light Sensitivity in the Human Brain.

My life is organized around the time on the clock, so I do not have the luxury of arranging my sleep around the sun’s rise and set. Therefore, I needed to manipulate my environment. When I began hacking my sleep at our apartment, my first light source to tackle was a street light that completely illuminated our bedroom through a high window in our cathedral ceiling. I had to buy a tall ladder just so I could climb up and cover the entire window with cardboard wrapped in velvet. Although we only had nearly-useless mini-blinds on all the other windows, this first light-reduction hack made an improvement in my sleep quality.

When we bought a house, the bedroom was the first room we remodeled. We set it up to be PITCH BLACK. The alarm clock is dimmed, there are no chargers or electronics in the room, and I added black-out curtains to the windows. Each night, when I first lie down to sleep, I cannot perceive a difference between having my eyes open or closed. (Of course, by the middle of the night, my dark adapted eyes can easily tell the difference.) If I step out of the bedroom in the wee hours of the night, the rest of the house seems so bright! There’s a light on the smoke detector, all the windows admit outside light, the microwave’s clock, the standby light on the TV, and on and on.

So my first suggestion is to get as close as you can to pitch black. Change things, move things, buy things, whatever — sleep is the most important part of your life.

The alarm clock

Initially, I had a generic alarm clock… beep beep beep BEEEEP! There’s nothing like waking up with a shot of adrenaline and cortisol to start me off on the wrong foot for the day.

First, I changed to an alarm clock which played music, but it had blindingly bright green numerals. Eventually I read about alarm clocks which have a bright light which slowly — over a half hour — fades up to fully illuminate the room. (Search for “Philips HF3470”; It’s discontinued, but it will get you going in the right direction.) Some mornings, the fact that “the sun has come up” in the room is enough to wake me up. But usually, the alarm clock proceeds to an audible alarm, and ours urges us by playing various tweeting bird sounds. (If I wasn’t so deaf, the light would probably wake me up enough to hear the actual birds outside.)

When to sleep

If you have all the above under control, you can technically sleep at any time of day. But there’s a catch: You need time to physiologically wind down before going to sleep. If it’s bright daylight when you want to sleep, you’ll need to craft a dimmed, calm space where you can relax and wind down. (But not where you actually sleep, don’t lay on the bed to wind down. More on not making your bed a multi-use space below.)

Consistency in sleep times is key. There are physiological processes which occur in the body which are not under conscious control. The body works on habit (and environmental cues) and it’s sluggish about changes. Wonky work shifts that make you change your sleeping patters are not healthy; if you’re into that type of work, just realize you’re trading your quality of life to accomplish your job. Be sure it’s worth it.

Remember: For me, sleep is the most important thing in my life. Work, play, scheduling, consistency… these are all things I’m will to work on, hack on, and change, to improve my sleep schedule because poor sleep leads to a poor life.


Slightly cooler works for me (and agrees with what I’ve read.) But it doesn’t seem to matter too much. As long as you’re comfortable. But if the temperature is consistently UN-comfortable, you need to correct that.

There are obvious ways to hack the temperature, (e.g., air conditioning, a fan,) but you can also hack the general room environment. Figure out where the air moves through the room. (For example, if air normally moves from your open window to the door, move your bed to be near the window.) Get creative and sling a hammock across your room and sleep close to the floor, (where it’s cooler in summer, or closer to the ceiling where it’s warmer in winter.) Find the room with the best sleeping temperature and move your bedroom there.

Different mattress and sheet surfaces will feel cooler or warmer, so experiment to find what works best for you. Different types and extent of clothing obviously matters, but have you actually experimented to see how what you wear (or don’t wear) affects your perception of temperature?


In general, splurge on things for your bed: Mattress, sheets, covers, comforters, pillows etc. Buy the most comfortable mattress, and the sheets you love to slide into. Then go another step and buy two sets of the sheets you love. (When you change the sheets you can strip and immediately remake the bed with clean linen.)

Improve the psychological comfort of your bed. Make changes, and build habits, which make the bed a comfortable, inherently relaxing, space. Room details such as color (hint: darker hues and blues are relaxing), lighting and general “busyness” of the room all have a subtle effect on your mood.

Slightly less obvious is to make your bed every morning. It doesn’t have to be fancy with specific folds or tucks, just make it up to whatever your definition of “made up” is. Later, each time you see the bed it will look inviting all made up, and you’ll look forward to peeling it open and sliding in.

Because it is a large, clear, open, space it will generally attract — but especially if you make it up each morning — random items throughout the day. Pay attention to what ends up on the bed and find proper homes, or invent systems, to keep those things off the bed. (For example: Clothes go ‘here’, worn-but-still-wearable items go ‘there’, pets are excluded by closing the door, put a chair in the room for sitting when dressing, etc.)


I’ve read various things about avoiding blue light in general, computer screens, TV, etc. But I’ve found that simply avoiding whatever it is that “winds me up” is sufficient to not sabotage my sleep. So, while I will look at my computer or phone near bed time, I don’t go to web sites or apps where I know I’ll get sucked down the rabbit hole. Instead, I’ll read through news feeds, e-books, or review my personal productivity systems and to-do lists. A lot of being able to readily fall asleep is related to my thinking-brain being relaxed. If there are things on my mind then I find I’ll be stuck laying awake in bed.


As with everything here, the key is to figure out what foods, and what eating times, affect your sleep.

I try to avoid eating within a few hours of going to sleep.
(In another part of this series, I’ll talk about intermittent fasting.) I find that I can sleep very well after a meal, particularly if I’ve had a couple hours for my digestion to get started.

What I’ve eaten also has a huge impact on my ability to fall asleep, and on my sleep quality. Too many sweets, or almost any amount of alcohol, to close to bed time will affect my sleep; I can fall asleep, but after an hour or so I find I’m wide awake. Same thing if I drink too much coffee. I’m pretty sure the stimulants (sugar, caffeine) and depressants (alcohol) affect my ability to reach the deeper sleep levels, and so I wake up instead of sleeping deeply. There’s a tremendous amount of information available about food and diet. Related to sleep, it’s worth looking into issues of digestion and experimenting to see what works for you.


There is solid evidence that Magnesium deficiency can cause sleep problems (restless legs, muscle cramps and more.) It is also a well-known relaxant. So that’s doubly suggestive that Magnesium (reading, experimentation, supplementation) could be very useful in improving your sleep. See Magnesium and Sleep.


There’s a lot you can do in terms of tracking sleep with things like Fitbits and Beddits. (Tracking is part of the “quantified self” movement.) Here again, the goal would be to measure something (sleep duration, quality, presence of sleep apnea, number of sleep cycles, etc.,) correlate that with how you feel and how it affects your life, and then make adjustments to your sleeping environment, habits and life in general. I did a small amount of tracking with a Fitbit. (I didn’t like the blindingly-bright green lights it uses for the pulse sensor. That’s how dark it is where I sleep.) But, for the period of time when I was tracking my sleep quality, it certainly helped focus my attention and efforts on improving my sleep.

Mental Activity

If I have too much on my mind, I sometimes have trouble falling asleep. When I first started working on my sleep I wasn’t yet journaling. Years later I started journaling and I found that emptying my brain in the evening was a wonderfully relaxing way to prepare for bed. Over the years, it became clear that as my time ran out each day, sitting down consistently to journal was difficult. So these days, I don’t regularly journal in the evening. (Instead, I write as part of my morning routine.) But sometimes I will journal to empty my thoughts if I feel that I’ve too much on my mind to readily fall asleep.

Room Usage

Don’t do anything other than sleep in your bed. Don’t read in bed, watch tv, or use digital devices. Whatever you do regularly, that is what you’re training yourself to do in that space. Have a “going to bed” routine, and turn out the lights.


For me, I can take a half hour blink-nap in the afternoon without it missing up my sleep. (A blink-nap is where I’m thinking, “I feel like I need a nap,” I lay down, blink, and a half hour has elapsed.)

Next up…

A few things I have not tried…

§6 – Sleep Epilogue

(Part 6 of 8 in ~ Changes and Results)

Here are a couple more things which I’ve read about, but haven’t tried as part of my sleep hacking.

Sleep journaling

Some people have suggested keeping a sleep journal. In it you record everything related to sleep: notes about your last meal (what and when), what time you go to bed, when you wake up, perceived quality of sleep, dreams… everything. You would then be able to review this sleep journal periodically and use it to inspire changes in your sleep rituals.

The best way to improve you sleep is to conduct experiments. Change some detail and then sleep with that for a month. Then review your sleep journal notes to compare with the previous month.

In my general life hacking, I was often changing many things at the same time. Some of the details of sleeping which you would hack on with a sleep journal, I was already hacking and tracking.

Sleeping alone

My Grand-parents’ generation seems to have slept more frequently in separate beds than is popular these days. (A quick search of the Internet leads me to believe as many as 1/3 of couples currently sleep in separate beds on a regular basis.)

I haven’t graduated to this level, yet. But I can tell you that having another person immediately next to you whose movements, or snoring, may wake you, is just another thing to mess up your sleep. When I first started hacking my sleep, I realized that we were waking each other up frequently in the night. It turns out that if I’m only sleeping lightly, the other person’s movements will wake me. But it seems that as my sleep quality has improved, movements and sounds are now much less likely to make me.

That said, if you wanted to try separate sleeping, you could try sleeping on the floor (with futon cushions, or air mattresses.) You could then move your bedding closer or farther apart as the mood strikes, and still be on a solid surface which would not convey any sense of movement from the other person. You’re still close enough, of course, that sounds could be an issue.

Aside: This is one reason why I prefer to sleep on my air mattress on the floor when I travel. Sharing a pull-out sofa or large bed with someone I don’t know, is the worst-case scenario for being disturbed all night.


(Part 7 of 8 in ~ Changes and Results)

This “Changes & Results” series is taking me much long than I had hoped. Meanwhile, some of the later parts are actually very interesting and would be useful to be able to have posted now. So this post is wedged in to mention these sections which are not yet published:

§7 – Exercise
§8 – Parkour
§9 – Changing My Feet
§10 – Twenty Minutes a Day
§11 – Walking to Mordor
§12 – Running

§13 – Intermittent Fasting

(Part 8 of 8 in ~ Changes and Results)

Intermittent Fasting (IF)

With any form of IF, you can get the same physiological benefits. The key is to find a form/style of fasting that works for you and which yields the results you want. No matter what you do, it requires [what may be] a whole new level of paying attention to your body; how you feel, how much you weigh, how strong you feel, how sharp your mind seems, etc. IF is putting your food consumption and internal eating-related systems on manual. That can be great, or it can be a car crash.

I’ve come to realize that the style of fasting I do is not actually me “doing something”, but rather me living in tune with my body. The way I ate previously was automated and not healthy. I started IF as a project, and now it’s simply more normal and healthy than they way I used to eat.


“Starvation mode” is not something you have to worry about with any of these short-term fasts. You’re not going to lose muscle (especially if you continue training or weight lifting). You certainly can exercise in the fasted state; I do just that all the time. I don’t eat until Noon and I’ve done all sort of ranges of activity in the fasted state.


Cells prefer to run on glucose. Things like muscles store some glucose internally and use that initially because it’s readily available. Some cells (notably, your brain cells) don’t store glucose and must have glucose from the blood. The liver stores glucose and releases it into the blood when glucose levels drop. When the liver runs low on stored glucose, it creates glucose from fat. In that process, the liver also create ketones (small, simple, alcohol-like molecules) which get dumped into the blood and will be removed by the kidneys or expelled in the breath.

Counterintuitively, some processes in your body (e.g., your heart muscle) operate more efficiently in the fasted state. When the liver adds ketones to the blood, your brain and heart prefer ketones as an energy source, which reduces your need for glucose to be produced by the liver. (If you do the deep dive on the biochemistry, it turns out that per joule stored in glucose versus in ketones, the heart can do more work per joule when using the ketones.) There is also a pronounced mental “feeling” of thinking sharper when your brain is using ketones. “ketone hacking” is an entire universe of people, information, podcasts…

What to Eat

Fasting is all about WHEN or HOW MUCH to eat. What to eat is a whole additional discussion. Some of the things you’ll read talk about what to eat, but I recommend initially focusing only on the when and how-much of eating. Then on subsequent reading and study, you could look at what you are eating and adjust that within the framework you’re settling on.

Types of IF

Aside from the various religious fasting prescriptions, there are two main variations: “eat, stop, eat” (ESE) and “16/8”. ESE is where you fast for a 24 hour period, once or twice per week. With “16/8” you fast 16 hours every day and have an 8 hour eating window.

I prefer the 16/8 because I like the regular schedule and I can always have lunch/dinner with people. (Most people don’t even notice I’m actually fasting in the morning.)


So that’s my overly-simplified introduction to the actual introductions to IF. I suggest starting here: