Dr David McGrath

Spine Physician

MB BS (Hons) FAFOM, RACP, FAFMM
Master of Pain Medicine

Periodic Cycles

1. Daily Day/Night Cycle
2. Daily Eat/Fast Cycle
3. Daily Sleep/Non Sleep Cycle
4. Exercise/Non Exercise Cycle
5. Monthly Fertility Cycle
6. Seasonal Earth Axis Cycle
7. Nasal Cycle (2-6 hours)

All of these cycles have Physiological effects with Different:
1. Periodicity
2. Amplitude of Effect
3. Phase relationship to each other

In other words, positive and negative effects upon our Homeostasis (wellbeing), depends on :
1. The Position on each cycle
2. Interaction between the cycles

This means that patterns under our control, 2,3,4 might have an ideal phase (timing) relationship to to the fixed cycles 1,5,6.

Again this a complex subject, but several facts and ideas, have already emmerged as important.

1. Night time workers, have an increased risk of heart disease
2. Eating before bedtime, can be associated with poor sleep
3. Seasonal affective disorder
4. "monthly" mood changes
5. Exercise in the afternoon/morning can be more satisfactory for some

(to be continued)