As well as managing the training over a long period during a fat loss phase, a reduced calorie intake required to lose body fat, also has an impact on recovery and other functions of the body, which can make dieting a stressor itself.
As a result, it can be difficult to use a linear approach whereby calories simply continue to drop over time.
Instead, a smarter approach can be to use a periodised dietary system, utilising higher and lower calorie periods. This can help to reduce the negative side effects associated with a prolonged deficit, to put you in control, rather than simply dieting to a point of fatigue.
A long term deficit can have an effect on 2 systems:
Psychological - this is potentially the most significant factor. Long periods of dieting can come with feelings of tiredness, fatigue and hunger. Short-term breaks from dieting can provide temporary mental respite from those factors, and help to continue the process of dieting with increased adherence.
Physiological - the reduced calorie intake can affect energy required for NEAT (daily movement), as well as training performance. Periods of higher calories can assist in providing more energy, and refilling glycogen stores, to keep daily activity high to continue the calorie burning process, as well as improve training performance to improve muscle retention.
Depending on the length of the diet, the deadline, and the size of the deficit, there are 2 main strategies to periodise calorie intake and to begin reversing some of the effects of dieting:
A diet break is simply a a planned period used as a break from dieting to reverse some of the negative effects of a prolonged diet.
Most effective with diets of 3 months+, and no deadline being affected as a result.