It can be quite easy to use throw away advice like ‘exercise more and eat well’ when giving advice about improving glucose stability.
Thankfully the team at Wahoo in collaboration with the Supersapiens Science team have recently done some digging (using the Wahoo integration with Supersapiens) to help find out more about what influences people’s glucose stability in free-living conditions with their findings being presented at the ACSM conference.
Unlike a laboratory setting, where conditions are very controlled, a free-living condition can be quite messy. This messiness should be embraced though when it comes to applicability, that is, life is messy and these sorts of pieces of research build some of the inherent confounding factors we may see in the real world into the research population. They are also as applicable to real life as science can be, after all, they are researching it. This is not to say this type of research is better as much as it is different and should not be discarded for not being laboratory based.
What did they do?
They followed 8 women and 27 men, for two weeks during their normal daily life. Individuals were told to live life as normal but to complete any exercise with a chest strap heart rate monitor. Additionally they used Supersapiens and logged their exercise (including RPE), meals (including macronutrients), sleep (and quality) and emotions (stress, motivation & fatigue).
What did they find?
The team found correlations between glucose stability and the number of cardio sessions per day, the number of grams of protein with the first meal of the day and the percentage of fat per meal. All of these correlated with more stable glucose whilst subjective feelings of fatigue correlating with less stable glucose (all p values <0.0001 aka very strong statistically).
The Supersapiens’ Take:
We should always ensure what we are seeing makes sense in the context of existing evidence and understandings of physiology. Of course, it always bears remembering that this sort of study is also one that shows correlations - rather than causation in much the same way ice cream and drownings are correlated by not causally related.
That said, the mechanisms underpinning many of these findings, or at least explaining part of the observations, are well known.
More frequent exercise will improve insulin sensitivity as well as playing a role in facilitating glucose absorption by the muscles (hence the benefits of post meal walking). Of course, high intensity exercise per unit of time will sensitize the individual to insulin more, but the nature of high intensity exercise is that acutely it may cause worse glucose stability as it can cause significant metabolic perturbations (much in the same way as it does with heart rate both of which should not be seen as negative, they are a net positive).
Increasing morning protein ingestion has been seen to have an impact of note in this case, likely not because of circadian differences across a day but more due to the nature of breakfast in much of the world. Breakfast seems to be the one meal relatively that is almost universally low in both vegetables (and with them fiber) and protein - both of which help stabilize glucose. So whilst this makes sense it is much less about the time of day as much as it is about the importance of protein in general and in glucose stabilization.
Similarly, the fat intake percentage stabilizing glucose makes mechanistic sense when considering that fat stabilized glucose itself but also in the context of protein being relatively fixed as a percentage of most diets. Thus increasing the percentage of fat will reciprocally decrease the percentage of carbohydrates - both factors of which have a glucose stabilizing effect.
Perhaps the most interesting and curious finding of this work was the correlation with increasing fatigue having a negative impact on glucose stability. Mechanistically this is more complex and more difficult to understand. Similarly the explanation could be due to a myriad of factors (which is the issue with correlation). Given this, Supersapiens will not speculate on the drivers of this. Having said that, appropriate sleep and recovery are the utmost to both health and performance with no significant downsides to them and thus should be the goals at all times.
Take Home Messages:
- Ensuring appropriate protein intake is key for health and athletic performance (especially recovery), the easiest place to increase this is at breakfast.
- Fueling for the work required is key - and having an appropriate carbohydrate intake is part of this. If concerned about glucose stability fiber, protein and fat can help with this.
- Increasing frequency of training/movement and/or reducing inactivity or sedentary time are great ways to improve metabolic health in general, as well as glucose stability.
For more tips on improving glucose stability see this blog article.
Gottschall, Jinger S.; Henderson, Neal A.; Cassin, C. Mac; Hastings, Bryce; Zignoli, Andrea; Skroce, Kristina; Lipman, David; Zisser, Howard. Greater Number Of Cardio Sessions, Protein For Breakfast, And Reducing Fatigue Can Minimize Glucose Variability: 2330. Medicine & Science in Sports & Exercise 55(9S):p 773-774, September 2023. | DOI: 10.1249/01.mss.0000987112.85936.98