Responses to exercise are determined by several factors: duration, intensity, type, frequency but also your quality and quantity of nutrition pre and post exercise.
Exercise changes can be increased by your nutrition. For example, it is well known the effect of protein feeding – if protein intake is low, then muscle protein synthesis (building of muscle) is low.
The link between nutrition, diet and exercise has been recognised since the 1800s, with nutrition playing an important role in the preparation for training.
‘’ ‘To the athlete of early times, the essential part and chief characteristic of training was not the taking of proper preparatory exercise, but the sudden and violent change of diet’’. ‘‘Going into training was taken to mean the commencement of a peculiar diet of half-cooked beefsteaks and dry bread and the reduction of the daily drink to a minimum, and not to imply the beginning of the proper training or cultivation of the muscles required for a race.’’ – Montague Sherman, 2005.
What is Periodised Nutrition?
Varying your nutrition intake in response to your training.
‘’Periodised nutrition refers to the planned, purposeful and strategic use of specific nutritional interventions to enhance the adaptions targeted by individual exercise sessions or periodic training plans, or to obtain other effects that will enhance performance longer term.’’
For example:
1. A focus on weight loss – lower energy intake
2. A focus on recovery, training and performance – higher carbohydrate intake
‘’Nutrition can be planned, as much as training can be planned – and can be made more purposeful’’ –
i.e. different nutritional methods are used to achieve certain/specific goals, like different training methods can be used to achieve certain/specific goals.
You need to build your nutrition plan around your training cycles and tailor your diet to suit changes in training duration and intensity. As your training changes, so should your nutrition.
Jeukendrup (2017) discussed various methods that have been used to optimise training, and linked us to other studies which show the adaptations brought about from the style of method.
Training Low
‘’Training with low carbohydrate availability’’ – little/no carbohydrate intake prior to exercise.
Training Twice a Day
Two workouts per day – First workout will reduce muscle glycogen, and then the second workout has little or no carbohydrate intake beforehand (low glycogen stores in liver & muscle).
It is thought that the muscles adapt to favour fat metabolism – Hansen et al. (2005) found improvements in markers of beta oxidation (breakdown of fatty acids) – 3-hydroxyacyl-CoA dehydrogenase (HAD) and citrate synthase (CS).
However – Yeo et al. found that cyclists who trained twice a day (training low), could not maintain the same intensity as cyclists who trained once a day.
Training Fasted
Workout after an overnight fast (last meal between 8 and 10PM), before breakfast, on an ‘’empty stomach’’. Muscle glycogen will be unaffected by the overnight fast, but liver glycogen will be very low.
Hespel et al. noted that fat utilisation for fuel was increased with fasted training.
Training with low exogenous carbohydrate availability
Low-Carbohydrate High Fat or Ketogenic Diets
One way to train is to remove carbohydrate from diet, and have a low-carbohydrate, high-fat diet.
In the 1920’s reducing carbohydrate intake & increasing fat intake caused high rates of fat breakdown, but also contributed to fatigue, and a reduced exercise volume.
Carbohydrate Restriction during recovery
Usually it is recommended to consume carbohydrate immediately after exercise, to help with glycogen synthesis/replenishment but this method of nutrition periodisation is the restriction of carbohydrate intake in the first hours after exercise.
This goes against the typical ‘consume carbohydrates post-exercise to speed up recovery.’
Sleep Low
Involves a hard workout in the evening , lowering carbohydrate availability followed by sleep with no carbohydrate intake.
There are minimal studies on this, with little known of potential side effects and effect on recovery/immune function and sleep.
Training High
This refers to – training with high carbohydrate availability. Both muscle and liver glycogen levels are high at the start of exercise, and/or carbohydrates can be supplemented during exercise.
Why?
Carbohydrates have been shown to be important to maintain and improve the the quality of training, reduce fatigue, and have an effect on intestinal function.
With a higher overall carbohydrate intake, reductions in training performance are less – with higher power outputs.
Train the Gut
Exercise is a stress to the body, and it is possible that the problems are caused by the fact the intestine is not adapted to absorb nutrients well under stress – with blood flow to the intestine being reduced during exercise (e.g. constipation, abdominal pains, diarrhea etc.) . The gastrointestinal (GI) tract is important to deliver carbohydrate & fluids during exercise and can affect performance.
Studies have shown that a high-carbohydrate diet increases the number of sodium glucose co-transporters in the intestines, which allows more carbohydrate to be absorbed during exercise.
Training Race Nutrition
Practice your nutritional intake plan for a race in the weeks leading up to the event. This may be for example, your drinking, caffeine intake, carbohydrate restricted/feeding etc. and can help and be a good dress rehearsal for the event, helping you see the responses to your nutrition.
Training Dehydrated
Studies have observed that dehydration reduces performance.
Supplements
- Leucine – stimulate protein synthesis (gain muscle mass/strength)
- Caffeine and Sodium bicarbonate – improve performance
Want to know a bit more? Have a read of Jeukendrup (2017) article which I have referenced at the bottom. The adaptions in the body are quite difficult to get your head around but it is an interesting read!
If you want a bit more information on how you could tailor your diet to your training sessions, please let me know! I may cover this in a couple of posts later on.
Jeukendrup, A. (2017). Periodized Nutrition for Athletes. Sports Medicine, 47(S1), pp.51-63.