“Afternoon diabetes” and nutrient partitioning

Don’t exacerbate afternoon diabetes with afternoon carbs.

Skeletal Muscle
As discussed previously [at length], insulin sensitivity in skeletal muscle follows a circadian pattern: starts out high in the morning and wanes throughout the day.

Diurnal variation in oral glucose tolerance: blood sugar and plasma insulin levels, morning, afternoon and evening (Jarrett et al., 1972)

 

impaired circadian glucose tolerance in the morning

 

Diurnal variation in glucose tolerance and insulin secretion in man (Carroll and Nestel, 1973)

Circadian variation of the blood glucose, plasma insulin and human growth hormone levels in response to an oral glucose load in normal subjects (Aparicio et al., 1974)

Adipose Tissue
And insulin sensitivity of adipose tissue goes in the opposite direction: starts out low, and increases as the day progresses.

Diurnal variations in peripheral insulin resistance and plasma NEFA: a possible link? (Morgan et al., 1999)
The studies were standardized for a period of fasting, pre-test meal, and exercise… Following insulin, NEFA fell more slowly in the morning (149 uM/15 min) than in the evening (491 uM/15 min).

Diurnal variation in glucose tolerance: associated changes in plasma insulin, growth hormone, and non-esterified fatty acids (Zimmet et al., 1974)
Adipose tissue insulin sensitivity is greater in the evening.  FFA are higher, and get shut down more rapidly, after a carb meal in the evening.

Summary: to minimize blood glucose excursions and proclivity for fat storage, eat more calories earlier in the day; this is circadian nutrient timing.  And according to the Alves study, a low-carb protein-rich dinner best preserves lean tissue during weight loss.


Diabetes Paradox
Interestingly, the circadian variation of skeletal muscle insulin sensitivity is blunted in patients with insulin resistance and/or obesity.  This is known as a “diabetes paradox” in some circles.

Diurnal variation of oral glucose tolerance: a possible pointer to the evolution of diabetes mellitus (Jarrett and Keen, 1969)
“In hyperglycaemic individuals the diurnal variation decreased as the blood sugar levels reached during the morning test increased, so that in a group of grossly hyperglycaemic men the mean morning and afternoon tests were almost identical.” 

Diabetes paradox

 

Further observations on the diurnal variation in oral glucose tolerance (Jarrett and Keen, 1970)
“In those with screening blood sugar levels >110 mg/dl, the degree of diurnal variation was least in those with the highest morning glycaemia… In a group of 40 control subjects, afternoon glucose tolerance tests yielded significantly higher post-glucose blood sugar levels. The degree of diurnal variation was significantly and inversely related to the degree of obesity.”

Afternoon Diabetes
Many of us have it to a degree, and one study suggested women may fare worse than men.

Does ‘‘afternoon diabetes’’ predict diabetes? (Jarrett et al., 1978)
Higher fasting glucose (pre-diabetic) = attenuated diurnal variation in OGTT.  ‘Afternoon diabetics’ more likely to become frank diabetics.

Circadian biohack
Collectively, these data suggest that skewing more calories earlier in the day, when insulin sensitivity is high in muscle and low in adipose, bodes better forbody composition and blood glucose control, and this doesn’t work if circadian arrhythmic or insulin resistant.  Get some blue blockers… they won’t fix everything, but it’s a start.


Part II: impact of circadian mismatched meal timing
(I’m honestly nottrying to become the “breakfast [in the morning] guy,” but that seems inevitable.)

Effect of breakfast skipping on diurnal variation of energy metabolism and blood glucose (Kobayashi et al., 2014)
Skipping breakfast resulted in higher 24-hour average blood glucose levels, by 6 points. That’s not a lot, but this was after only one day… and since skipping breakfast is a circadian mismatch, this likely won’t improve over time. Also, are you surprised?  Skeletal muscle is naturally more insulin sensitive in the morning; this is a good time to eat.

breakfast skipping


Acute effect of late evening meal on diurnal variation of blood glucose and energy metabolism (Sato et al., 2011)
“The present study under controlled sedentary condition supports the notion that a single late evening meal enhances 24-hour average blood glucose by 4 points.”  That’s not a lot, but this was after only one day… and since late night eating is a circadian mismatch, this likely won’t improve over time. Also, are you surprised?  Skeletal muscle is naturally more insulin resistant in the evening; not a good time to carb-load.

late evening meal

 

The second-meal phenomenon is associated with enhanced muscle glycogen storage in humans (Jovanovic et al., 2009)
“The rise in plasma glucose after lunch was significantly less if breakfast had been taken, despite comparable insulin responses.” In circadian biology, there’s talk of a food-entrainable oscillator (FEO); kind-of-like the importance of timing of light exposure (LEO), meal timing is also important.  Breakfast [in the morning] seems like the optimal time to kickstart the FEO.

Collectively, these studies confirm that eating out of sync, when muscle & adipose are less & more insulin sensitive, respectively, results in elevated blood glucose levels.  Over time, no bueno.

Second-meal effect: low-glycemic-index foods eaten at dinner improve subsequent breakfast glycemic response (Wolever et al., 1988)
A low glycemic index dinner is similar to a small &/or low carb dinner due to its minimal impact on metabolic homeostasis.  Compromise?  Have a low net carb, protein-rich dinner.

low net carb, protein-rich dinner

Prospective study of breakfast eating and incident coronary heart disease in a cohort of male US health professionals (Cahill et al., 2013)
Breakfast skippers had a 27% higher relative risk of coronary heart disease, and late-night eaters had a 55% higher risk… I imagine these numbers are so much higher than the 4-6 point increases in blood glucose because this study was over the course of 16 years; the others, 1 day… also, don’t rip off my head for citing an epidemiological study just yet; rationale is further explained below.

Skipping breakfast and late-night carbs cause elevated 24h average blood glucose (Kobayashi, Sato, & Wolever), exaggerated glycemic response to meals (Jovanovic), and are correlated with metabolic deterioration (Cahill).  Given the short-term intervention studies and the sound physiological rationale predicted by circadian biology, I suspect there’s a good deal of causation in that there correlation.

Conclusions
Optimal: eat more when the tissue-specific circadian regulation of insulin sensitivity is high in muscle and low in adipose = earlier in the day.  If circadian mismatched, FIX IT… these biohacks simply won’t work as well in that condition.

Nutrient timing > CICO.  Period… however, all of this is assuming a a plant-based, low net carb, whole foods template.  And a protein-rich breakfast; not typical breakfast food crap.

Don’t exacerbate afternoon diabetes with afternoon carbs.

calories proper

 

 

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  • Cheesy

    Hi Bill, what happened to the previous version ? Your site was down for quite a while. All comments have gone …

  • Disruption of circadian insulin secretion is associated with reduced glucose uptake in first-degree relatives of patients with type 2 diabetes
    http://www.ncbi.nlm.nih.gov/pubmed/10535452/

    this further suggests the diurnal variation in muscle insulin sensitivity is blunted in patients with insulin resistance.

    • Cheesy

      Wow, that sucks for the FDRs … so there is some genetic component to this ??

      • the implication is that there is a genetic/epigenetic component. And yeah, it sucks :/

  • This Old Housewife

    Whatever the site was taken down for, it didn’t help the virus situation–in fact, it got WORSE! I just picked up and killed off 6 in one visit. I just signed up for your newsletter so I won’t need to visit here every day. That way, I’ll know if they’re after you or me.

    • thank you thank you thank you for these updates! very helpful.
      I bit the bullet and outsourced this problem to a team of malware assassins… so if the problem is on my end (and I think it is), it is being dealt with as we speak 🙂

  • Hey I just found this blog and you present very clear and unbiased science! I had two questions for you. Firstly, this new idea in paleo land that low carb is not what we should be on ( resistant starches etc) – any thoughts?

    Secondly, I just hit ketoadaptation today (Ketones 0.5mmol/L), but have been low carb (low carb, mod protein) for two weeks. I had Thalassemia, which is a genetic disorder that stops your body from binding iron. It isn’t too serious because I only have one chromosome with it, but I have always had a low iron count to the point that I couldn’t give blood. And it isn’t about taking more iron because it’s about binding the iron not consumption quantities. Anyways I got my blood tests done and I now have normal iron and it’s binding with normal ranges. Here are the blood tests if interested – http://saturatedinfats.com/2014/09/27/ketogenic-diet-has-eliminated-thalassemia/

    Do you have any idea what might be happening here? The doctor said to me that my blood tests were amazing!

  • Cheesy

    Hi Bill, just to update you, so far so good on swapping things around. I am still not terribly hungry in the AM but I manage to get the bulk of my calories. I have a light dinner early like 5pm (yesterday was makret fillet, olives and a bit of aged cheese). Today is my weekly ~ 40h fast so no foods at all since 5pm yesterday. I may resume eating earlier than usual (tomorrow morning). I also have to say that I have not experienced any real difference in terms of energy and sleep quality. I will probably better assess things after a couple of months, once my appetite has time-shifted 🙂

    • Thanks for the update!

      unless you had chronic sleep problems to begin with, I wouldn’t really expect sleep quality to drastically change…

      that said, I’m curious about hunger. Theoretically, fewer calories later in the day *should* make you hungrier in the morning… eventually…? Or is AM hunger just biologically low…

      I’m rarely very hungry in the morning, but when I have a big breakfast, I’m rarely very hungry later in the day.

      • Cheesy

        Re hunger: I have been an early evening eater for a really long time, so I guess it takes some time to adjust …

  • Cheesy

    From the Alves study (conclusion in abstract) :
    “Moreover, eating carbohydrates mostly at lunch and protein mostly at dinner had a deleterious impact on glucose homeostasis”

    Mmmm, does not sound good, does it ?

    • No, that doesn’t sound good…. unfortunately, it’s bollixed! (imo)

      I made a chart for you 🙂

      Here’s the full text http://bit.ly/1BvOBI8, and a brief breakdown of the of the body comp results http://disq.us/8kalyd

      • Cheesy

        Thanks, I will look into the papers more closely.

        • Sure. Even the body comp results weren’t very compelling.

  • Bill, were you personally a breakfast skipper and now changed things around? Just wondering since I pretty much skip and then eat increasingly more towards the end of the day (albeit I train at 19:00).

    • Hey Mash (“Mash”?),

      A lot of studies show that skewing more calories earlier in the day bodes well for body comp & metabolic health… and there is a relatively logical explanation – ie, circadian regulation of tissue-specific insulin sensitivity http://caloriesproper.com/carb-back-loading-take-ii/

      • Thanks, I am busy going through your articles, and listened to your chat with John.

        (Guessing you read the comments outside of the articles as I am commenting on your ‘“Afternoon diabetes” and nutrient partitioning’ post.)

        Interesting stuff indeed, and I am going to have to rethink things now or at least give it a shot. I wonder though that with evening training this whole thing might be a bit skewed [as you mention in brackets], and worth taking advantage of at least having the majority of carbohydrate PWO.

        For “people like my mum” as I say, having the less exercising individual “front-load” carbs and calories might make more sense, and basically shift the “overnight” fast back so it starts earlier and ends at breakfast. I.e. lower calorie early dinners.

        (Techy nickname when my email address was thomash@ to make matters worse we have had some ISSN thread conversations on FB where my name is “Toma”).

        • here’s my 30000 foot view of exercise timing: if you take a big breakfast, the circadian regulation of insulin sensitivity takes care of nutrient partitioning (ie, don’t *need* to exercise)… so I guess this would apply to “people like your mum.”

          If you take a big dinner, then you need to exercise to offset circadian muscle IR & adipose IS.

          • In other words, is your priority big dinner or evening training?

            if priority is big dinner, then evening training is “damage control,” not “optimization.”

            if priority is evening training, then it’s less clear… almost all of the meal timing studies support AM calories; I don’t see how PM exercise could drastically reverse this.

            but then again, my notorious disclaimer: these are small pieces of a big puzzle. If PM exercise + big dinner = better adherence, then stick with it 🙂

          • OK so I have always held to the following “habits”:

            – Breakfast: Extend overnight fasting for increased ketone circulation.

            – Lunch: Keep carbohydrate low and fats higher to potentially “maintain” the previous point for longer.

            – Snack: Consume enough carbohydrate and protein early enough before training (rock climbing / resistance in my case) to maximise glycogen stores + amino acid circulation during workout.

            – Dinner: Consume enough food post-training to hit daily macro targets, take advantage of increased muscular glycogen storage, and provide nutrition for loosely termed “overnight recovery” (slower digesting protein i.e. larger meat portion).

          • ^^^ looks pretty close to CBL

          • Cheesy

            I think, considering the evidence of what you say, that the big breakfast thing is something many people should follow, provided that their circadian rhythm is not out of whack!

            For me, it’s been a few days and I must, I enjoy it 🙂 I usually work out around 1pm but don’t eat big around this WO. I had so much food this morning (around 7am) that my dinner today has been about nothing, just a little scrambled eggs, a bacon slice, some chocolate and a little bit of ricotta cheese … As I said somwhere else, if you want to control your hunger, eat some legumes … they keep you full …

          • sounds great! I’m glad it’s working out for you 🙂

          • “the big breakfast thing is something many people should follow, provided that their circadian rhythm is not out of whack!”

            intriguing statement 🙂

            I’ve been thinking a lot about this… and actually, I think this might be even more reason to get in line with a more circadian-appropriate eating pattern… to re-entrain circadian rhythmicity via the food-entrainable oscillator

          • johnnyv

            Possible counterpoint in leaner and fitter individuals.
            http://www.leangains.com/2012/06/why-does-breakfast-make-me-hungry.html

            Suggesting cortisol augmented insulin release to meal soon after waking.

            Personally the thought of food in the morning disgusts me so I would not want to personally follow a big morning breakfast strategy.

          • “Personally the thought of food in the morning disgusts me so I would not want to personally follow a big morning breakfast strategy.”

            I would not argue against this! …in part because I don’t think it’s *that* big of a deal for healthy people / much more leeway in this population

  • Gus Q.

    Hi Bill,
    If you are following Kiefer’s Carb Nite Solution so you are ultra low carb for 6.5 days is there really going to be a big difference between whether your once per week carb meal is in the morning vs. the night? And may I also ask if there would be a difference for a “healthy” individual, a pre-diabetic individual, and a diabetic individual? Let’s also assume (for all 3 individuals) a resistance training session the following day…
    Thank you,
    Gus Q.

    • Hi Gus,
      CNS is a much more reasonable approach than CBL for most people… the studies cited in this blog post are more like CBL, where carbs/calories are consumed later in the day, *every day.*

      If carb-loading only once per week, morning may still be optimal, but due to such a low frequency, as you said, the difference won’t matter as much.

      There are some data showing the circadian variation in skeletal muscle insulin sensitivity is blunted in diabetics (the “diabetes paradox”), although I don’t think this should be interpreted to mean that evening carb-loads are superior to morning… adipose is still going to be very receptive to the effects of insulin in the evening… but again, if it’s only once per week, the difference won’t matter as much (especially if also exercising in the evening).

      • “Let’s also assume (for all 3 individuals) a resistance training session the following day…”

        If by this you mean evening carb-loads followed by morning exercise… this might work for some, but not because of biology. Exercise should ideally be performed around the carb-load, chronologically, to bolster skeletal muscle glucose uptake and suppress excess insulin signaling. I wrote more about this here: http://caloriesproper.com/insulin-sympathetic-nervous-system-and-nutrient-timing/

        • Gus Q

          Thank you so much for the quick response. I am going to read this article right away. I have no “science” but personal experience I get great results from fueling (glycogen refill) workouts the night before (morning workouts especially but also afternoon). It obviously fits the “lifestyle” very well which I can see in all of your responses to others is a very important factor. None-the-less it’s nice to know what is optimal! And just because something works for me doesn’t make it optimal or will necessarily work for someone else…
          Thanks again!
          Gus

          • You’re welcome 🙂

            On that note – (I tried to stress this in a few of my replies) – lifestyle, convenience, & adherence are relatively big factors, compared to exercise timing… if trying to “optimize” exercise/nutrient timing causes adherence to slip, then definitely just do what works for you. These are small pieces of a big puzzle 🙂

          • Gus Q

            I did see that I didn’t go a good job of letting you know that it was very clear…
            Just for information. Friday night is usually a “carbload” after being ultra low carb all week. Then an amazing nights sleep. Saturday morning I have 2 spoons of 94% MCT coconut oil and some small form of protein and caffeine OF COURSE. I make a protein shake and hit the gym. I’ll have a the protein shake either halfway through or at the end. I like to train on an “empty” stomach but I don’t want to be “empty” (if that makes sense) hence the coconut oil. Saturday mornings are usually long and intense workouts and so far so good.

          • Thanks for clarifying. Sounds like you’ve got it pretty well-tuned!

            “I make a protein shake and hit the gym. I’ll have the protein shake either halfway through or at the end.”

            this statement reminded me of a post I wrote about ‘protein timing’ in relationship to exercise. Not entirely relevant to your situation, but it makes a case for earlier rather than later… this still shouldn’t interrupt the “fasting” aspect of your training protocol, just some food for thought 🙂

            http://caloriesproper.com/nutrient-timing-op-101/

          • that said, I also wrote an-entirely-other post about the benefits of exercise in the fasted state: http://caloriesproper.com/cyclical-ketosis-glycogen-depletion-and-nutrient-partitioning/

          • Gus Q

            Putting everything together I think I will try to have my shake as early in the training session as possible and keep everything else the same or similar. Even still this is a change I have either been skipping the PWO shake entirely (with the exception of Sat morning) or having it when I get home after the training session. And again for information sake when I train during the week it is late afternoon not morning.
            I am a “strength athlete” a novice powerlifter but I am not solely interested in JUST maximizing strength. I also want the best body composition possible.

  • Meal timing influences daily caloric intake in healthy adults http://bit.ly/1CHsD7n

    Tl;dr: AM breakfast ftw

    “Results suggest that later relative timing of meals, particularly eating close to sleep, could lead to weight gain due to a greater number of eating occasions and higher total daily caloric intake.”

    • Cheesy

      Hey Bill,
      Big thumbs-up on the big AM breakast! After 2+ weeks, I must say it changed something. I was far from obese but I actually leaned some more … I must eat less overall for sure! I really like this new habit and I will continue the experiment for some months. Glad I kept reading your blog 🙂

  • Børge Fagerli

    Looking at your first citation: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1789199/pdf/brmedj02186-0021.pdf, and calculating HOMA-IR scores for insulin sensitivity at 60 minutes postprandially, but insulin sensitivity is best at 3 pm (under 50 group) or 8 pm (over 50 group), not 9 am. That’s dominated by liver and muscle.

    The morning breakfast and insulin sensitivity issues seem to be more relevant in obesity, and not that critical in leaner subjects – and when you throw high intensity exercise into the mix it seems to even out things…but it is becoming very clear that the higher fat intakes should be placed earlier in the day at breakfast and lunch.

    • – grasping at straws –

      glucose clearance is WAY better at 9AM than later in the day. In this study, it’s at least partly due to ?insulin secretion, but saying it’s the other way around and citing HOMA-IR..? nope

      “The morning breakfast and insulin sensitivity issues seem to be more relevant in obesity, and not that critical in leaner subjects”

      but the circadian variation in insulin sensitivity is greater in lean people (devil’s advocate)

      • Børge Fagerli

        Good point, and I am not grasping at straws – I am just trying to make sense of it all with the seemingly conflicting research. If you don’t recommend high-carb breakfast to take advantage of this (for some reason I can’t access the comment section on the CBL thread, I only get the mobile version of your site), I was assuming that it would necessarily mean more fats (and protein)? Why be so adamant about insulin sensitivity for breakfast if you don’t recommend a high-carb breakfast or even higher carb intakes in general? I would think it was more relevant to look at the fate of fats via HSL and LPL activity, lipolysis/oxidation rates etc.

        And all the papers I have looked at point out that the night-day cycle is reversed in humans vs. rodents, so I was of the assumption that a higher calorie (meaning higher fat) intake in the early part of the feeding cycle would have the same effects in humans as in rats…and the Wilson study seems to confirm this?

    • 1) “high intensity exercise into the mix it seems to even out things”

      in this context, exercise is damage control, not optimal (which would be doing everything in the morning).

      2) “higher fat intakes should be placed earlier in the day”

      …just need to substitute the word “calorie” for “fat.” Keep in mind the studies which simply flipped the calorie burden (AM vs. PM) while keeping macro’s the same, showed better results with AM calories.

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  • James L

    Hi Bill. Followed you on Twitter for a while and I’ve enjoyed reading a lot of your work recently. I have been using a CBL approach, whereby I train around 7am and again at 4pm (high volume resistance training, sprint & sled work mainly) . I consume 99% of my daily carbs after the PM session (and higher calorie meals) . I consume just protein and fats between sessions. Regarding AM consumption of calories as being optimal for body composition – would you recommend taking on carbs and higher calories after my AM session – as opposed to consuming them post PM session? If the goal is to manipulate fat loss and increase lean mass simultaneously. Then limit carbs & calories post PM session.
    Would be interested to know how you would approach a ‘two a day’ session in my position.

    Thanks
    James

    • Hi James, thanks!

      that’s an interesting scenario: assuming roughly similar intensities at both sessions, I’d shift it to something like 60% of calories around the AM gym session & 40% around the PM session (or at least 50-50) (adjust these estimates if you’re eating > twice daily).

      …maybe there’s not a strict “anabolic window,” but I’d hate to see you fasting all day after a heavy AM session.

      As to the timing of carbs, most of the data follow calorie timing — we just seem better at dealing with them earlier in the day. PM exercise improves PM carb tolerance, but still wouldn’t match AM carb tolerance in your case, because you’re exercising in the morning, too.

      Hope this helps!

      • James L

        That’s really helpful, much appreciated. Looking forward to trying something different. Thanks!!

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  • Raymund Edwards

    Insulin sensitivity in skeletal muscle follows a circadian pattern: starts out high in the morning and wanes throughout the day.

    So muscle can easily feed on fatty acids in morning ( OK to be fasted now )

    And insulin sensitivity of adipose tissue goes in the opposite direction: starts out low, and increases as the day progresses

    So in morning adipose easily releases those fatty acids to feed said muscles

    IN early evening – TIME to eat what has been caught on the hunt 🙂
    fatty acids now can be better stored for next day activity ( done on empty )

    Seems to me things are a little different when low carb ( and eating one meal ) and seems to fit with ancestral pattern – who wants to go hunting weighed down with overloaded belly ?

    Also a lot find this more natural and easy

    What do you think Bill ?

    ” Baker Pasha (Sir Samuel Baker) ascertained that fact in studying the habits of the Abyssinian hunters. Youngsters of twelve years join the hunting expeditions of their tribe and think themselves lucky if the kettle can be set a-boiling to the extent of furnishing a good evening meal. In the repose of the kraal they might yield to the temptation of a noon-time lunch; but when game is scarce, think nothing of rolling themselves up in a blanket at night and trying a nap to forget the disappointment of the day, trusting to the chance of better pot-luck for the morrow. “Qui dort dine,” say the French—”he who sleeps feasts.” A good night’s rest in the bracing night air of the Abyssinian tablelands will sustain strength even on the basis of alternate day meals. A daily feast is so abundantly sufficient that active youngsters would fear to handicap themselves by re-loading their stomachs before the end of the next day. With the prospect of an up-and-down hill race against time and the competition of athletic companions, the offer even of a moderate morning lunch would probably jar upon their sanitary conscience. ”

    BERNARR MACFADDEN

    • In the evening:
      “TIME to eat what has been caught on the hunt 🙂
      fatty acids now can be better stored for next day activity (done on empty)”

      I tend to agree: eating more later in the day is a very efficient way to accumulate fat mass 🙂
      …as you mentioned, if you choose to eat this way, it is best accompanied by intermittent fasting & regular exercise.

      • Dan Ordoins

        I choose to fast in the AM and have my larger meal around noon or sometime after (post hunt/ fasted exercise/ activity). In this sense I am feasting on my reward of a successful hunt. My one to two meals following are lighter and my last meal is 3-4 hours before bed so in sleeping on a light stomach and into a fasted state again. Evenings may be a walk and activities of preparing for the next day or bonding with family. Just looking at it from perhaps and evalutuinary circadian rhythm cycle.
        Myself I have been doing this (daily morning fast) for over 6 years with great sucess in both health and body comp. been Keto or VLC for around 3-4 years.
        I would say though that this may not work for someone over weight and or not healthy. I am sure context matters and reigns King.

        • “I am sure context matters and reigns King”

          +1 🙂

  • bradjkovacs

    Which of these studies controlled for training? In real world context, this only seems like an issue for sedentary individuals (which most of society is, I grant that). If an individual strength trains regularly in the afternoon or evening, it’ll change hormonal milieu and affect adipocyte/myocyte sensitivity to glucose.

    • my 2 cents (way oversimplified, but whatever):

      1. PM exercise is a hack that’s useful *if* you want to eat more of your total daily energy intake in the evening. Not optimal meal/exercise timing, imo.

      2. eat more in the morning, in which case exercise isn’t necessary bc muscle & adipose insulin sensitivity yada yada yada….

      3. or better still, do #2 and exercise in the morning.

      4. if lifestyle limits exercise time to evening, I dunno, maybe split calories 50/50 (AM/PM), w/ more protein peri-workout..?

    • P.S.
      I’d LOVE to see the study: exercise AM vs. PM, with more food in AM vs. PM.

      Outcomes: metabolic parameters & body comp.

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  • Kris

    Where does seasonal eating come in to play regarding this? i.e. in winter here it’s pitch black by 5 PM. Does this mean the window for consuming carbs is correlated with light cycles? i.e. a shorter window in winter for optimal insulin sensitivity in muscle tissue?

    • yes, I think so, best to time meals with light, year-round.