Why timing matters

Knowing what to do or what supplement to take doesn’t cut it anymore. Knowing what and why is great but there’s another dimension that is often neglected and that is to ask the question of when.  While it is easy to get lost in the minutia that is increased knowledge of genetic signaling pathways and training adaptations, this increased body of knowledge also provides us clues to that question of when to do things.

Timing is critical for one simple reason; it can completely alter, boost or negate, the training effect that you are working so hard for.  Why spend so much work suffering through a workout or trying to do certain activities to maximize recovery, if by simply popping a pill or having the wrong order of exercise you can significantly negate the previous work.  We’ll delve into some of the examples of where timing matters, but more importantly I hope that you start to ask the question of when to do things and if it matters.  It’s a question that we don’t have all the answers to, but one that is overlooked and deserves investigation.


In a recent article on competitior.com  I raised the question of whether caffeine is always a good thing in terms of performance.  One of the messages I was hinting at was that when you take caffeine matters.  Taking it before a workout or race decreases some immune system response, while taking it after can keep the CNS “up” for a bit after being taxed, which might make you feel better in the short term but repeating too often could potentially lead to some not too desirous effects.  So when you take it in terms of the workout, and before what workouts matters heavily.  As suggested in the article, deciding the timing of when to take caffeine and when not to is critical.  Find a balance


I’ve written about this topic numerous times and by now the message might be a bit bland, but free radicals and oxidation occurs during endurance training, and it just so happens that it’s a signal for adaptation.  The main pathway it affects is the PGC-1a pathway which leads to mitochondria increases.  What happens when you take antioxidants is that it minimizes the activation of this signaling pathway therefore negating some of the exercises benefits.  A couple years ago this was a somewhat theoretical argument, but the evidence keeps mounting.  Recently, in Keith Baar’s lab they found that antioxidants did in fact suppress PGC-1a.

The question is if you still insist on popping some Vitamin C, E or any other antioxidant for reasons such as increasing iron absorption with Vit. C, then when can you do it?  Unfortunately, there’s no clear answer, but its clear that when you take them matters.  Take it right after the workout and you just suppressed adaptation, take it far away from it and nothing happens to the workout.  Of course there aren’t enough hours in the day, so what’s the gap needed?  There is no answer, but I subscribe to a 2 hour guideline.  Why 2 hours? Because if we look at a few studies that have looked at PGC-1a activity, it peaks at 2hrs versus other times tested closer or further away from the workout.  Therefore, space it out by 2 hours if you need to take it.

Another issue of timing mattering is that it depends on what the workout is as to whether or not you need to follow the rule. In general anything that stresses oxidation and adaptations such as mitochondria increases (so anything hard or long..) counts.  On the contrary, if you are looking for hypertrophy from a strength workout then, you might actually want to take antioxidants afterwards.  Why? Because in this case metabolic stress decreases the signal for adaptation for hypertrophy. So if you are a weight lifter, pop that Vit C if you want post strength session.

For those wondering what about fruits and all those wonderful foods that contain antioxidants, it’s pretty interesting but it seems like doses in vitamins are the problem and not the natural occurring ones.


Another one I’ve covered numerous times so I won’t delve too far into it, but in this case inflammation is another signal for adaptation.  The key is normal or just above normal inflammation is a signaler, not crazy excessive inflammation (as if you sprain your ankle horribly).  Once again, when you take it matters.  A study looking at taking anti-inflammatories during ultra marathons showed that inflammatories actually increased inflammation. So that might not be a good idea.  On the other hand, taking certain NSAIDs before a race has occasionally shown to modify pain perception and therefore increase performance.  Lastly, other research has demonstrated that taking anti-inflammatories post workout decreases training adaptations.  So, once again, three scenarios of timing, three different outcomes.  My recommendation is to follow the 2 hour rule again post workout for the most part, for similar reasons.


Over at Sweat Science, Alex went over a study that showed that when you take iron post workout impacts how well it is absorbed.  The general consensus was that taking iron within 6 hours of a hard or long workout decreases absorption.  This is of particular interest for female runners trying to increase iron stores.  If you continually take iron post workouts, maybe that’s one contributing factor that is creating the situation of you fighting an uphill battle in getting ferritin levels up.


In 2009, when I was still training and went over to Europe with my friends and training partners Mo Joseph and Nikeya Green, one of the things I noticed was other athletes in our little group in Leuven were popping some meltonin.  Why?  Because adapting to the time change sucks…horribly… so much so that in our little dorm style rooming for the first few days we had an empty dorm room which was designated the can’t sleep room where if you were up at 2am and couldn’t sleep you’d just go there and see who else couldn’t sleep and hang out.   Anyways, the popping of melatonin is an interesting one because it works!  But only if taken at the correct time!  If you take it at the right time, it actually really hurts you adjust to the time difference.  Of course, none of us knew that then, but it’s a great example of timing mattering.

Without getting so complex that I don’t understand anymore, according to a review by Waterhouse (2007, Lancet)  melatonin “delays the body clock after waking and advances it in the afternoon and evening.”  So essentially if you take melatonin when your body is naturally low on it, it shifts the body one way, while if you take meltonin when it normally is high in the body it shifts the body the other way.  So it depends if you are looking for a phase delay or phase acceleration in terms of taking melatonin.  As for general advice when to take it, on YOUR body time, taking melatonin between 4pm and midnight causes a phase acceleration, while taking between 1am and 10am YOUR current body time causes a phase delay.  So what time you are used to matters when you take melatonin. So, if I’m travelling from Portland to Europe and it’s 6pm and I pop some melatonin to help me get to sleep, it’s actually 10am my body clock time…so I’m setting myself back that first night potentially! Every night shift that by an hour or two until fully adjusted and you have a decent rule of thumb. Similarly, timing of light exposure matters and is another good example of this whole timing thing, but that’s another example.


This should be an obvious one but sometimes the obvious ones are the easiest to overlook, but when you do certain workouts, it matters.  We can use endless examples here, but we’ll stick to a few of my favorites and hope that you all can figure out the rest.

One that I always cite as a classic example is that the training adaptation changes based on if you do strength training before or after endurance work.  The two pathways competing for adaptation interact and can help turn each other “on” or “off”.  So if you do strength training and then follow it up with a good little run, you’ve shut off the pathway for muscle growth (which could be good or bad depending on what you’re training for).  Additionally, we can look at some recent research that showed that how you adapt neurally depends on the timing of what was done first.  This applies to not only endurance versus strength timing, but also the sequence of your strength training workouts.

Another quick example, is the timing of long runs or runs following long runs.  When we are looking at training adaptation signals, one is a decrease in muscle glycogen.  Once we are low on glycogen, some sweet adaptations take place to signal our body to deal with this better next time. It depends on the case, but sometimes it’s a good thing to train low.  So there are two ways to look at this beyond relying on the long run to get the glycogen decrease effect.  If we look at doing a long run and then 10hr later (i.e. long run in evening followed by next morning run), the glycogen stores certainly aren’t restored.  So using a long run followed by an easier but still relatively long run is a good way to get double the low glycogen (i.e. 17mi followed by a next morning 10miler).  Another option which I employ occasionally with my runners is the Friday workout followed by the Saturday long run.  The Friday workout (especially if its something like a threshold run) can decrease glycogen just enough so the next day you’re starting with low stores and can dig a little deeper into glycogen depletion on the following days long run.  It’s a great way to increase strength endurance.


Finally, timing matters in recovery enormously.  Take carbs in at the right time post workout and you maximize insulin sensitivity and replenish glycogen slightly faster.  Take protein at the correct time and in the correct amount and you increase protein synthesis.  Or take an ice bath at the right time and your legs feel good and poppy the nest run while take it at the wrong time and your recovery is hampered and you feel a bit flat.

I’ve discussed the above situations before, so I won’t go into detail, but one I’d like to expand on is protein ingestion.  Of course taking it in during/after strength training in certain cases can increase protein synthesis promoting repair and growth.  But one thing that most distance runners don’t think about is protein ingestion throughout the day.  When I was in grad school, me and my fellow classmate, Matt Andre, who is getting his PhD at Kansas, would spend time after class throwing out theories together.  One we came up with is whether taking a hit of protein before bed or even in the middle of the night would increase protein synthesis and therefore recovery.  Similarly, with an athlete I coach we were experimenting with ways to increase recovery and came up with the idea of taking “hits” of 20g or so of protein every few hours to kind of give protein synthesis and the hormonal profile a boost.  Well, it turns out we weren’t that crazy after all.  At a recent nutrition conference put on by some heavy hitters in the science at GSSI, these topics were both brought up.  It’s pretty exciting to see actual research backing it up, but the lesson isn’t that we were on the right track, but that timing of when you take stuff matters! It’s more than just total calorie or protein counts that matter.Secondly, we were just theorizing without much data to go on that we were aware of at the time.  So think for yourself and if it makes sense give it a go.

These are just a few examples of the importance of timing which you can learn from, but the real key is getting you to think about when you do things and if it matters.  Don’t overthink it as sometimes it doesn’t make a difference, but ask the question anyways.  Being inquisitive and curious is the key to being a good coach.

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    1. M. Mann on April 17, 2012 at 2:40 am


      I'm still slightly confused about the timing of a weight lifting session. I coach a high school team and I can only do my running workouts and weight lifting in a 3-4 hour window after school. Should the weight session (heavy sets of squat, deadlift, etc) come before the running workout, or after? I have been doing it after since I wanted the bulk of their energy for the running workout.

      • Nick Clinton on May 7, 2012 at 3:49 am

        Steve prove me wrong if I am, but I've heard your body's energy pathways of Anaerobic and Aerobic cannot both be open at the exact same time, and where weightlifting is more anaerobic and running longer runs or recovery runs are more aerobic (in college our recovery jog days were followed by strides, plyometrics, stretching, core exercises, and weightlifting), you can train the fuel pathways to switch over quicker, but typically it's going to be one or the other working and then recovering. So running and then lifting (or vice versa)causes the body to suppress the natural recovery process for each pathway individually and not allow that advantage of training and fully recovering that singular pathway. I've heard it's better to lift after or before about 5-6 hours of a run to effectively train both, and preferably on hard workout days because those days use more anerobic activity (not like anyone would want to lift after a hard workout). Of course this is impossible with only a 3-4 hour window, which is why I didn't start this style of training until after I graduated. I doubt it's terrible to do both together though as long as you're taking those protein hits throughout the weight session and getting plenty of sleep. Any truth here?

      • Brendan McCormack on April 21, 2013 at 10:32 am

        NIck: With any sort of exercise, the aerobic energy system is supplying energy. When the workload becomes great enough, the anaerobic system must add in to accommodate the higher energy demand. The anaerobic system utilizes a very finite system of energy, turning pyruvate into lactate. This is limited in endurance because as the the levels of lactate and free hydrogen+ increase, they limit the body's abilities to perform the necessary reactions to continue. This system is very fast but provides very little ATP per pyruvate (net gain of 2) The aerobic system uses a much more efficient system by sending the pyruvate through the mitochondria. This results in far more ATP per pyruvate but is far slower (net gain of 32-36)

        The aerobic system "recovers" by returning the body to homeostasis and resting levels of pH and blood content. This process requires only time. The anaerobic system "recovers" by returning muscle lactate, blood content, and pH levels to resting and restoring muscle and liver glycogen stores. This requires time and carbohydrates.

        As long as the running portion of the workout does not require high speed or a large "kick," it could be performed at optimal levels as soon as the body recovers from the aerobic exertion of the weightlifting portion. This means that the running portion should follow the strength portion as the body should be fully rested when it requires high levels of technique and the full support of both the aerobic and anaerobic energy systems to avoid injury, while the running portion does not require the same level of support to remain injury free.

        Reference: Senior Majoring in Exercise Science

    2. Anonymous on April 17, 2012 at 8:51 pm

      good read. thanks steve

    3. Anonymous on April 19, 2012 at 4:42 pm

      Great information-good to see your articles coming back more often- know your busy, but appreciate you sharing your knowledge with us.

    4. My Marathon Training Program on April 21, 2012 at 8:52 am

      "Timing is critical for one simple reason; it can completely alter, boost or negate, the training effect that you are working so hard for."

      I must agree with this quote. At some point, we runners have done some things that we regret because we are not patient enough to wait for the right time. Timing is indeed, everything.

      Good job with this post! You've just earned another reader!

    5. Anonymous on April 23, 2012 at 2:08 pm

      "Because in this case metabolic stress decreases the signal for adaptation for hypertrophy."

      Do you have a reference for this? My understanding was that this was not true, as a few studies has suggested that metabolic stress does play a beneficial role in hypertrophy.

    6. RichD on May 7, 2012 at 5:15 am

      Steve, I enjoy your blog. It would be great if you posted the date of the entry at the top of it. Otherwise you don't know if an entry is recent or four years old. Right now, you have to find out the date using indirect means, like hovering over the posting time at the bottom, or going to some month's archive to find entries by month. Thanks.

    7. Anonymous on May 23, 2012 at 12:07 am

      You brought up lots of interesting things to look for but never provided a single answer. Left me not learning a thing…

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