Q11 Periodised Carbs

Question 1

Mechanism/ Theory

Answer 1

Extremes of the spectrum: high carb and keto
- trained cyclists who were keto-adapted had much higher rates of fat oxidation at 64% of VO2 max

Based on fact that glycogen stores are finite and body fat stores are practically limitless

Train low; race high theory

• low muscle glycogen could stimulate adaptations such as citrate synthase activity
• enhanced fat oxidation
• low muscle glycogen elevates circulating FFAs and catecholamines
• enhanced mitochondrial adaptations

Sleep low; train low
- study on trained cyclists found improved time trial

Periodisation (Fuel for the work)
- selective sessions are with restricted carbs, but where the goal of the session is maximal performance, high carbs is key

Question 2

Dose/ timing

Answer 2

Ways to implement periodisation:

• sleep low train low
• when there is two sessions in one day restrict carb intake after the first one, so carbs are low for the second one
• prioritise carbs around sessions goals

Train low only for moderate intensity sessions less than 90mins
- fuel with protein to avoid muscle breakdown

Race day and train high sessions

• studies show 1 day of carb loading to be as effective as 3
• consume 8-10g/kg
• during consume 60g/hour

Question 3

Negative circumstances

Answer 3

Optimal periodisation is not well known yet

May have increased adaptations/ fat oxidation but does this correlate to performance improvements

some negative implications to training

• desired intensity is unlikely to be maintained as carbs are crucial fuel source
• immune system function can be suppressed
• muscle protein breakdown is increased
• body can no longer utilise carbs as effectively so may effect race day performance (down-regulation)