A lot of people get caught up in the confusion of whether to bulk or cut, and often take it to the extremes beyond benefit.
So, what are they both?
A “bulk” is essentially a period of massing, eating in a surplus with the intention of gaining strength and hypertrophy (muscle growth). As a consequence, fat gain often occurs. This is totally natural, as of course, you are going to gain weight if you eat more than you burn.
For a massing / gaining phase, research suggests a 0.25-0.5% increase in bodyweight per week is optimal for muscle gain and fat minimisation.
Anything above this is likely to compose of body fat, so while you may be enjoying a ‘dirty bulk’, you may be impacting your potential fat minimisation, which will become harder to “cut” down later on. This applies particularly if you are a competitive bodybuilder/figure competitor, whose muscle definition and visibility is crucial. You should gain for a minimum of 2 months for optimal hypertrophy.
Moving onto “cutting”. A “cut” is the opposite of a bulk; a period of leaning out/eliminating some unwanted body fat.
A fat loss phase should aim for a 0.5-1% weekly body weight loss. However, this of course will vary on a day to day basis as a result of daily fluctuations (included but no limited to water intake, carb intake and therefore glycogen water retention etc). Again, a slower approach wins the race with fat loss as well as muscle gain, but in this case to minimise muscle atrophy (decrease in muscle size). In order to preserve as much lean muscle mass as possible, research conducted by Eric Trexler concluded a maximum of 1.0-1.5% of body weight loss per week. The research found that some people would prefer a slower “cut”, lowering calories more gradually while others prefer a harsher “cut” for a shorter period of time. Both had very similar results and therefore it is best to do which most suits you!