When is low in Carbs a “No No” for the Endurance athlete

When is low in Carbs a “No No” for the Endurance athlete


Silhouette Of An Exhausted Sportsman At Sunset

When is a diet lower in carbohydrates not a smart strategy for the endurance athlete?

And when is lower in carbohydrates during training season NOT recommended for the athlete aiming for weight and body fat reduction? When in general a lower in carbohydrate diet is recommended for that very purpose?

low carb
Low carb meals aren’t always appropriate for the hard training endurance athlete

In general endurance athletes do NOT need as many carbohydrates during day to day training as many out dated dietician texts will have us think. Given there will be those on either side of the extreme needing much more or much less carbohydrates to support optimal training, recovery and health.

Carbos like this are not on the plan for my athletes!

processed carbs

In general in the A-C Health Solutions clinic I recommend low to moderate carbohydrate intake on most training days. These fuelling carbos can come from oats (or millet, quinoa or buckwheat porridge flakes), root vegetables such as beet, squash, potato and sweet potato, banana, dried or fresh fruit and small portions of cooked grains such as rice, millet, quinoa, buckwheat, amaranth, etc.

Carbohydrates are ideally timed before and immediately after training and only on high volume or intensity training days (i.e. for then you need them… makes sense eh?). The plate should be mostly vegetables, with a decent palm-sized protein intake, include some healthy fats (avocado, virgin olive or coconut oil, nuts, seeds, pastured organic butter, pastured animal fats, oily fish, etc.) and then as needed your small portion of carbohydrates.


On lighter volume training days or days off then you probably don’t need this many carbohydrates and are best sticking to a nice portion of vegetables with a small portion of root vegetables and no grains.

steak and veg
Steak and roasted veggies
Omelette with veggies
Omelette with veggies
Grilled fish with steam-fried vegetables

In general we tend to think of meals as recovery and eat more after higher volume days; however don’t forget that your evening meal is also preparation for the day ahead. And so if you have a hard day the next day such as a LONG training run or cycle or a strategic training RACE then I do recommend that you are more liberal with your carbohydrate portion at dinner time and then have another snack containing a small to moderate carbohydrate serving (with some protein and fat) before you go to bed (e.g. oatcakes with hummus; rice cakes with almond nut butter; second small serving of dinner; banana+berry and vegan or casein protein + coconut milk smoothie; yogurt+nut butter and fresh fruit, etc.).

No athlete is the same in their macronutrient needs.

Some endurance athletes require a high intake of carbohydrates to maintain energy, performance, recovery and stable weight.
Others gain fat at the sight of a potato and most lie somewhat in between….. with a natural daily variance depending on training demands, work and life demands, sleep, stress, hormones and menstrual cycle phase for example.

I do believe that the fitter the athlete gets and the finer tuned their athlete engine and body then the higher the metabolism and so the greater overall food intake that is required….

And don’t forget that the endurance athlete’s engine runs on a lot of fat and so it makes sense to be vigilant at including a source of healthy fats in your diet on most days…. these fats don’t make you fat; they fuel your performance, recovery and even more importantly are the precursor ingredient to your hormones.

My personal inspiration and ideal for health 🙂

Easier days, key sessions, and certain less intense and shorter sessions may permit taking your carbohydrate intake far lower than I mention above if you are aiming for body weight cuts, and body fat shrinkage to get you to a better racing weight (improved strength and power ratio). This strategy works well provided that  your recovery is holding strong. If recovery is poor then you are on a fast track to burn out when you push your diet too low in recovery carbohydrates and for too long. (What does it feel like to be recovered? You feel fresh, muscles feel good, energy is good, pulse and blood pressure are stable and normal, no postural dizziness, motivation is good, sleep is good, no coughs colds or feeling run down and the menstrual cycle is regular as a brief guide).

On these lower in carb days up your veggies, fats, and protein from healthy options – this isn’t aitkins! A low-fat and low carb diet is lunacy – I will only say this once. If you don’t believe me get on google and read some science papers about the importance of fats for health, sports performance, hormone balance, stress tolerance, and mood.


Even if you are on a lean cutting phase, certain key sessions will require you to raise carbohydrate intake: for example longer training runs or 2 hour plus cycles, training competitions such as faster 10 km to half marathon distance or as some discovered this weekend (at Keeper Hill Challenge) hectic downhill racing which cause a lot of eccentric muscle damage.

Muscle trauma due to down hill running is actually far greater than up hill running and the damaged muscles do not replenish fuels very well, thus you may need slightly more to recover as not all cells are up to speed recovering glycogen (aka fuel) and so the recovery process can be significantly delayed and the post running pain experienced far greater….


It is obvious why longer in duration sessions will require more carbohydrates before training for fuelling and during and as recovery to support metabolic and hormonal recovery. However when there is greater than normal levels of muscle damage anticipated or when this is experienced after the event (in other words poor preparation) then glycogen replenishment is impaired somewhat and muscle damage is exacerbated; recovery takes even longer. So this effectively leaves you extra stiff, sore or KNACKERED for longer than normal possibly resulting in subsequent missed sessions. To speed recovery you actually need more carbohydrates than normal (but not a pig out all the same).


See the study linked below as an example of finding supporting the theory that eccentric muscle damage hinders glycogen replenishment.

So it makes sense to raise your carbos somewhat for these key sessions to fuel best training or race performance and subsequent recovery meaning you can return to your normal training schedule faster. The extra carbs balance out when you consider less days or key intense training sessions might be missed versus the extra fat burning you may have gained keeping it lower in carb for that one day.

Make sense?

Happy training peeps.


Ps ginger, turmeric, omega 3 fats from salmon, red and purple coloured fruits and vegetables and green tea are awesome to speed the recovery of sore stiff muscles oh and an Epsom bath, stretching and a deep tissue massage if you can bear it!



Eur J Nutr. 2004 Jun;43(3):148-59. Epub 2004 Jan 6.

Further glycogen decrease during early recovery after eccentric exercise despite a high carbohydrate intake.

Zehnder M1, Muelli M, Buchli R, Kuehne G, Boutellier U.



Delayed onset muscle soreness (DOMS) is a well-known phenomenon of athletes. It has been reported from muscle biopsies that the rate of muscle glycogen resynthesis is reduced after eccentric compared to concentric exercise.


Try to compensate by a carbohydrate (CHO)-rich diet the decelerated glycogen resynthesis after eccentric exercise, measured by magnetic resonance spectroscopy.


Glycogen, phosphocreatine, ATP, and Pi were measured in the human calf muscle. Twenty athletes divided into two groups (DOMS and CONTROL), reduced glycogen in M. gastrocnemius during two different running protocols. Additionally, 12 DOMS subjects performed an eccentric exercise while the CONTROL group rested. Subsequently, subjects consumed a CHO-rich diet (> 10 g/kg body mass/24 h).


In both groups, glycogen has been reduced by about 50%. The first 2 h after exercise, glycogen dropped further (-15.6 +/- 15.7 mmol/ kg ww) in the DOMS but rose by +18.4 +/- 20.8 mmol/kg ww in the CONTROL group (P < 0.001). CONTROL subjects reached resting glycogen within 24 h (137 +/- 47 mmol/kg ww), while DOMS subjects needed more than one day (91 +/- 23 mmol/kg ww; P < 0.001). Pi and Pi/PCr, indicators of muscle injury, rose significantly in the DOMS but not in the CONTROL group.


The diet rich in CHO’s was not able to refill glycogen stores after eccentric exercise. Glycogen decreased even further during the beginning of recovery. This loss, which to our knowledge has not been measured before is probably the consequence of muscle cell damage and their reparation.

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