Spike Insulin Post-Workout?

Diet and Nutrition
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Excerpted from the first issue of Alan Aragon’s Research Review:

Quote:
Is It Necessary to Spike Insulin Post-workout?

Another concern of the fat-free-post-workout camp is the blunting of the insulin response. The rationale of maximizing the insulin response is to counteract the catabolic nature of the post-trained state, switching the hormonal milieu into an anabolic one, thus speeding recovery. Although this might benefit those who train fasted or semi-fasted, many don�??t realize that a pre-exercise meal (and in some cases the mid-exercise meal) is doing more than enough spiking of insulin levels for anticatabolic purposes.

It�??s an important objective to not only maximize muscle protein synthesis, but also minimize protein breakdown. However, the latter doesn�??t require a massive insulin spike, but rather just a touch beyond basal/resting levels. To illustrate this, Rennie & colleagues found that even during a sustained high blood level of amino acids, no further inhibition of muscle protein breakdown occurred beyond insulin elevation to approximately 15 μU/l,20 which is slightly above normal basal levels of 5-10 μU/l.

To reiterate, the pre-exercise meal can have profound effects on insulin levels that surpass the length of the training bout. Tipton�??s team found that as little as 6g essential amino acids + 35g sucrose taken immediately before exercise (45-50 minutes of resistance training) was enough to keep insulin elevated to roughly 4x above fasting levels 1-hour post-exercise.21 It took 2 hours post-exercise for insulin to return to resting levels. A similar insulin response was seen with 20g whey by itself taken immediately preworkout.22 If carbs were added to the pre-training protein, there would be yet a greater insulin response.

As far as solid food goes, Capaldo�??s team examined various metabolic effects during a five hour period after ingesting a meal composed of 75g carb (47%), 37g prot (26%), and 17g fat (27%).23 Although this study didn�??t examine training effects, this meal would make a nice post-workout meal due to its absolute (and proportional) amounts of protein and carbohydrate. The fat-fearing camp would warn against the meal�??s fat content interfering with the insulin response. However, this meal was able to raise insulin 3 times above fasting levels within 30 minutes of consumption. At the 60 minute mark, insulin was 5 times greater than fasting. At the 300 minute mark, insulin levels were still double the fasting level.

Elliot and colleagues compared the effect of fat-free milk, whole milk, and a higher dose of fat-free milk (to match the calories of the whole milk) taken 60 minutes post-resistance exercise.24 Whole milk was superior for increasing net protein balance. Interestingly, the calorie-matched dose of fat free milk containing 14.5g protein, versus 8.0g in the whole milk (an 81% advantage), but still got beaten. The investigators speculated over the possible mechanisms behind the outcome (insulin response, blood flow, subject response differences, fat content improving nitrogen retention), but end up dismissing each one in favor of concluding that further research is necessary to see if extra fat calories ingested with an amino acid source will increase muscle protein synthesis. Lingering questions notwithstanding, post-workout milkfat was the factor that clinched the victory �?? at least in overnight-fasted subjects.

To put another nail in the coffin of the insulin spiking objective, post-exercise glycogen resynthesis is biphasic.25 Unlike the subsequent �??slow�?? phase which can last several hours, the initial �??rapid�?? phase of glycogenesis lasting 30-60 minutes immediately post-exercise is not dependent upon insulin. Maximizing post-workout hyperinsulinemia may be beneficial for athletes with more than a single exhaustive endurance-containing training bout separated by less than approximately 8 hours, but in all other cases, the benefit in �??spiking�?? insulin is nil.

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I guess I’m not understanding how both statements can be true…?

No, I don’t think insulin spiking is necessary, but it is well-known to be effective for recovery and protein synthesis.

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All this is a great discussion and a cool experiment if you work in a lab and want to have some fun in your free time, but for practical application my belief is that its like splitting hairs. Not sure if you will be able to find some guys who are bigger than others and find out that the secret behind that is “spiking insulin” after workouts, UNLESS its an actual insulin and by spiking you mean injecting.

Unless you do everything with your food and workouts as stupid as you can think of on purpose, you probably get like 85% of what you can get out of it. Now spiking insulin, meal timing, intra workout nutrition, optimal rest times between sets, optimal reps each are worth like 0,5%-1,0% extra gains.
So if you really live like a robot and do anything by the book, and your newbie gains are long over, we are talking what here… like you can gain maybe 2-3lbs of muscle a year natty. Adding some 5-10% is not even visually noticable in a year or even 2-3 years combined.

When i was into all the sciency stuff i really expected that each thing i learned and applied to make a noticable difference. It never did.

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FWIW Mat Fraser, the 5x CrossFit Games Champion, always spikes insulin after training.

You’re right that a lot of the sciency stuff is super nuanced and has little affect, but insulin spiking post-workout is one of those that actually works.

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Not gonna say it doesnt work, but since you say it does… how can you tell?

And Rich Froning doesnt. So… It seems that insulin spiking doesnt work too well…

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Insulin spiking replenishes glycogen in the muscles, which leads to better recovery - and therefore better performance in subsequent training sessions. Additionally, natties have good protein synthesis, but not great (unlike enhanced lifters), so the insulin spike and related protein synthesis capabilities make it particularly effective for the natty trainees.

Rich Froning is amazing, but does not entirely stack up to Matt Fraser. IDK if using him as a counterexample really proves a point; insulin spiking is well known to enhance training performance and recovery… why do you think powerlifters eat gummy bears and shit while they’re training?

To get to the point of “how can you tell”… Try training on low-carbs, then try training on high-carbs. Which one did you perform better on?

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I understand the theory behind it, but what i was asking is… how do you know it works or that it works in a way that it matters? Before/After progress pics of someone who did not spike insulin for 3 years and then did it for 6 months got same amount of gains or smth?

Yes it is, im not fighting against this. I am asking - how can you tell that it matters? Do you have made significant(visually noticable) gains more when doing this? Care to show progress pics?

I actually prefer training completely fasted and continue fasting for hours after the gym also. I felt my best, when i fasted the night, trained at like 10AM, and my first meal started at like 4PM.

Eating carbs is also known to induce “carb coma” which is why people get sleepy after lunch, so eating definetly gets a lot in the way of how good i feel in the gym.
Sadly, i have to eat to get in the calories, but im definetly more slow and sluggish if i eat before/after the gym.

Basically what i hate about all this is that no matter what articles say, people only have their beliefs in “oh yea, i feel sooo much better” but they dont make more gains anyways. They are stuck in the same shape for years believing in supps, or programs, or insulin spiking or everything that looks cool in lab results, but rarely anyone can actually SHOW how well it works. And if no one can show it, why do we still think it matters?

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Well, I think we both know that these methods (and science) are far behind quantifiable results which could be easily compared, so I doubt you (or anyone) will get such pictures.

Gains aren’t linear, so it’s not like you will put on more size later in your ‘career’ than doing so earlier - but I can say that I’ve done quite well as natty, with >45lbs muscle added from post boot-camp (a time where many skinny enlisted folks gain muscle). Whether this is due to insulin spiking or not is up for debate, all I can say is I’m on the farther right side of the distribution scale of muscle mass while natty.

This is true, but training has so many variables that it makes it really hard to narrow down what caused one person to grow more than another. The best results of this would be shown by tracking workout improvements while insulin spiking compared to when not insulin spiking… This is the most significant effect of using this tool anyways.

Protein synthesis is great, but if ~15% better synthesizing is accomplished, each training session is still only adding a few grams of muscle tbh. Still, leveraging enough of these small “helpers” can lead to much better results if done over time. This is the game natties must play, whereas enhanced folks typically get away with not leveraging such benefits.

Blind faith? :joy:

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Id say that enhanced folks should get MORE out of these leverages, but…they dont. No one does. Even if you put those 2% extra gains on steroids and double them, they still arent noticable.

Yea. Thats my problem with this.
Any time someone says that he knows what works - its only blind faith because no one has anything real to show for it.

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They wouldn’t need to, and in this particular case - the enhanced trainees don’t get the same leverages a natty would. Protein synthesis for enhanced folks is great 24/7, whereas natties have fluctuating protein synthesis. So the “anabolic window” really is a myth if enhanced, but kinda accurate for natties (except it’s more like 2-4 hours post-workout instead of 30 mins).

Yeah, because enhanced folks will just inject insulin, rather than spike it with food… so in reality, it does work and is noticeable - but they aren’t playing around with a Snickers bar for the same effect.

If the insulin spike didn’t work, no one would be toying with HGH and Insulin - alas, here we are =)

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The article doesn’t say not to spike insulin post workout. It said don’t wait around, eat before training, and spike insulin pre workout.

And that waiting to spike insulin post workout would be the most beneficial to dude’s who trained fasted.

I like this author, but his stance confuses me. He’s against “nutrient timing” (when it’s Intra or Immediately post workout) and his proof that you don’t need to worry about it is studies using different nutrient timing (food pre workout).

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I used to be carb phobic and greatly preferred to train fasted, and I still think fasted training can be used to raise GH levels, but keep in mind that androgens substantially block the cortisol receptors in muscle cells meaning that protein breakdown is held very low and most amino acids broken down during training and fasting can just be recycled and used to rebuild. 5 grams of net protein accrued per day would amount to over 20 pounds of muscle mass in a year so the recycling of amino acids (rather than turning them into glucose and urea) can have a greater impact on nitrogen balance than increased protein synthesis.

We know what the protein synthesis curve looks like after hard training. Protein synthesis rises steadily, is about 50% above baseline after 4 hours, about double baseline levels from 12-24 hours (maybe a little higher in the middle) and comes back to baseline by about 36-48 hours (shorter if you have a longer training history), so increased protein synthesis is actually highest from about 4-30 hours after training.

Insulin directly turns on mTorr even without training or Leucine in the diet.

I also have worked with type I diabetic athletes in an extremely close setting with continuous monitors of blood glucose and precise knowledge of insulin in their system. Something I think people may be missing is that it’s not the insulin per se, but the insulin levels x insulin sensitivity that determine the anabolic affects of insulin. Insulin sensitivity is DRAMATICALLY increased during hard higher rep weight training. What would normally be near basal levels of insulin can be very powerful during hard training although if stress hormone levels get very high the reverse can start to occur.

One reason that fasted training made me feel good is because when insulin is lower cortisol goes up and cortisol in the short term makes people feel good. I would train fasted and raise my cortisol levels and they would stay high for hours. Since peri-workout carbs reduce the cortisol spike from training, they make you more insulin sensitive over the next 12 hours too because the eliminate the counter-regulatory effects of cortisol. My cortisol from 8:00 am training could still be elevated by midnight when I trained fasted.

My work with type 1 diabetic athletes would suggest to me that insulin sensitivity can be at least 500% as great during intense training, and can remain higher than normal for 8-12 hours after training hard. This is because of non-insulin mediated glucose uptake in muscles combined with the fact that insulin circulates much faster and more directly to the working muscles during training.

There is a big difference between spiking insulin before training and after a warmup. Spiking insulin before training can put supra-physiologic levels of insulin in the bloodstream and then the training raises insulin sensitivity and can make you go low. Taking in fast carbs starting after a warmup probably raises insulin levels very little because glucose is sucked into muscles without insulin during that period. 75 grams of glucose starting after a warmup won’t even raise my blood sugar over 100. If I take it 30 minutes before training I will crash to under 60 during training. If I take it and don’t train I can rise to 150.

I usually take peri-workout carbs because they lower my cortisol the rest of the day and that also improves sleep quality. I also can lose fat with no muscle loss.

Also, low rep strength training, even though it has the highest peak power output requires less glucose. The reason is that you can power 6-12 seconds of maximum output just from ATP and creatine phosphate and if you rest long enough you can restore that from fatty acids (no need for carbs). Carbs become more important when sets go above 5 reps an rest periods drop to under 3 minutes because fatty acids cant keep up with ATP restoration at those workloads.

Now what about spiking insulin 4-30 hours after training? I’ll think about that and respond next…

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Yeah, that’s what I’m after.

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Where is the article? Through my experience, I absolutely do NOT believe in spiking insulin during a workout to supra-physiologic levels. If you train hard and take in cyclic dextrin (the main benefit of is that the larger molecules pull far less water into the stomach to make it much easier to handle during hard work) you can easily take in 50 grams of glucose polymers immediately before or during the warmups of that 1 hour workout and not much insulin spike. I have seen insulin dependent athletes take in 50 grams of glucose in an hour and not require ANY added insulin above their basal levels that we all have in our bodies all the time. SO, high insulin in your system during training is not the key because insulin sensitivity is so high during moderate rep weight training. What you are doing with that 50 grams of glucose is slamming it into muscles with normal insulin levels due to high sensitivity and other factors around training. At least this is true if you are not in a hypercaloric diet or training to the point of hormonal insulin resistance.

So there is a big difference between taking in fast carbs, waiting for insulin to surge and then training, which will make you hypoglycemic, and taking in carbs right before training and training your ass off to force the glucose into muscles with normal insulin levels. For every gram of glucose you force into your muscles you will break down one less gram of protein, or glycogen.

Just because insulin levels don’t get very high that way does not mean that insulin is not working to signal hypertrophy. It is working, but it is working better because the muscles’ sensitivity to insulin is better, and particularly the muscles that are being trained (while just raising insulin tries to put glucose indiscriminately into the liver, non-working muscles, working muscles and works to block the release of free fatty acids from fat cells. Intra-workout glucose directs the glucose to the working muscles and even a little available glucose can reduce protein breakdown over the next 20 hours.

In fact, supraphysiologic levels of insulin during a workout not only direct glucose EVERYWHERE and shut down fat mobilization, but if it makes you hypoglycemic it will raise cortisol even more.

Getting glucose to the working muscles during the workout is even MORE important IMO when in a calorie deficit because that is when you may end up with progressive glycogen depletion that ends up slowing down your metabolism.

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Let me modify my response. When trying to loose bodyfat and retain muscle, I prefer to take in carbs after I have warmed up on my first exercise. This insures that I won’t need much insulin exposure to force the glucose into muscle because they will be very insulin sensitive and also experience non insulin mediated glucose uptake during the hard training.

If I was in a growth phase where I was eating a little above maintenance to gain muscle I probably WOULD take in glucose in advance of training by 15-25 minutes to raise insulin levels but would HAVE to also continue to take in additional carbs throughout the workout to prevent hypoglycemia because if I downed 35 grams of glucose plus leucine 20 minutes before a workout then I would be training hard WITH high insulin in my system. I have had blood sugar drop to 55 from that, and THAT can cause cortisol to rise too (it is an independent stressor that can have catabolic effects downstream. You may need to match your pre-workout carbs with an equal or even greater amount of carbs during the workout to balance the insulin released from the pre-workout carbs.

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I’m glad you kept thinking about it! That was a great post.

I guess seeing the timing of the carbs weight loss approach (taking advantage of insulin sensitivity) vs the weight gain approach (increase insulin) really boiled down everything else you said into easy to understand and usable info.

Thanks a lot for taking the time to circle back and make sure I wasn’t lost in the weeds.

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