1. Nutrition

5-Day Fasting Diet

Although fasting has only become a popular mainstream diet in recent years, this is another protocol Vince Gironda recommended way back in the 20th century. 

Vince observed that eating heavily over extended periods of time would result in a heavy build-up of mucus in the intestinal tract, which would prevent the proper digestion and absorption of food. 

A sign that this is happening is constant bloating, lethargy, and a loss of muscle gains. 

When a bodybuilder presented these signs, Vince would prescribe the 5-Day Fasting Diet to clear out the intestinal tract, thus allowing the digestive system to work properly and prepare the bodybuilder for a subsequent phase of muscle growth. 

A ‘Bridge’ Between Diets

There’s no question that many of Vince’s bodybuilding diets were tough. 

However, the reward for enduring such challenging dietary protocols were massive muscles and stunning levels of definition, enabling them to stand out on the bodybuilding stage and impress the judges. 

Following the completion of his diets, Vince may recommend a break from bodybuilding nutrition and advise the bodybuilder to follow a short-term nutrition plan to act as a ‘reset’. 

In addition to the 5-Day Fasting Diet, the other diets Vince kept up his sleeve for this situation were the Lacto-Ovo Vegetarian Diet and the Complete Vegan Diet. 

Instead of directly improving body composition, these diets simply acted as a ‘bridge’ and were positioned directly between two different diets, such as the All Protein Muscle Building Diet and the Maximum Definition Diet. Alternatively, they could be used as a starting point before commencing a longer-term diet, such as the Maintenance Diet or the Weight Gaining Diet. 

Essentially, each of these diets served a similar purpose – 

  • Rest the body by reducing the workload on the digestive system
  • Clear out toxin build-up 
  • Re-ignite the ‘taste’ for protein 
  • Enhance protein digestion and metabolism 
  • Enhance nutrient absorption 

Of these three diets, the Lacto-Ovo Vegetarian Diet could be sustained the longest and was used on occasion to directly help Vince’s clients shed body fat in a short space of time (actors and very overweight clients). 

The 5-Day Fasting Diet and the Complete Vegan Diet were both variants of the same protocol, whereby the bodybuilder would consume a reduced food intake over five days, in order to clear the digestive tract of accumulated toxins, mucus, and metabolic waste products, which would leave them better prepared for upcoming nutrition plans. 

One such diet these plans frequently followed was the  ‘36 eggs a day’ nutrition plan, which would often leave bodybuilders with a strong distaste for eggs. Vince needed a way to turn this around quickly so they could begin consuming nature’s most powerful muscle-building food once more!

The Downsides To Excessive Protein Intake

Following a high-protein diet for an extended period of time creates a number of downsides. 

Firstly, it can become quite tedious. Eating excessive quantities of one food can result in ‘taste fatigue’, where the individual completely loses the desire to eat that particular food. In the case of high protein foods, this can be problematic, especially for those who want to build and shape their muscles. 

Secondly, eating high quantities of protein-based foods for months on end, at the expense of other foods, can result in nutritional deficiencies. 

Third, protein is the most complex macronutrient for the body to breakdown digest, meaning it’s a lot of work for the body. Over time the digestive system can become overwhelmed and less efficient at digesting protein, which can make building muscle a challenge. 

Finally, there is also a risk that eating too many high-protein foods can increase the build-up of various toxins within the body. 

Therefore, Vince designed the 5-Day Fasting Diet to overcome these problems and enable the bodybuilder to begin digesting protein again so they could go on to create a fantastic shape. 

When To Use

The 5-Day Fasting Diet was typically used to overcome stalled progress, as a result of the body no longer being able to optimally digest and absorb protein. 

When this happens, the bodybuilder will struggle to recover from intense training and muscle building will become impaired. 

Therefore, fasting was like hitting a nutritional ‘reset’ button.

The aim of the 5-Day Fast is NOT to drop maximum body fat and emerge looking like a shredded adonis…

But rather to ‘repair’ an overwhelmed digestive system prior to commencing a new diet, or if necessary, as a mid-diet break in order to make the current diet more effective by allowing for enhanced protein digestion.

As well as being used following high protein nutrition plans, the 5-Day Fasting Diet could also be used prior to their commencement, such as the All Protein Muscle Building Diet, since it would increase the bodybuilder’s ability to digest and metabolize protein, which would make the diet more effective, and increase muscle building potential. 

Training During The 5-Day Fasting Diet

A key thing to remember was that the 5-Day Fasting Diet wasn’t a diet designed to help improve bodybuilders’ muscle mass or definition, therefore, training wasn’t strictly necessary. 

It’s also worth noting that Vince often recommended fasting following intense training and nutrition, during which the bodybuilder was advised to rest. 

Should a bodybuilder wish to continue training over the five days, they would be permitted to, but not intensely. This is because they will not be consuming enough food to fuel their training, nor will they have sufficient nutrients for recovery, meaning that intense training protocols could result in burnout and/or injury. 

5-Day Fasting Diet Breakdown

Although in the strictest terms, fasting means the complete absence of food, Vince actually discouraged this practice with his bodybuilders. 

Vince noted that when people followed a strict ‘no food’ protocol, there were some unpleasant side effects, including:- 

  • Chills
  • Dizziness
  • Headaches
  • Blood pressure problems
  • Cramps
  • Diarrhea
  • Insomnia
  • Indigestion
  • Gas
  • Vomiting
  • Reduced pulse rate
  • Heart palpitations

It’s also worth noting that total fasting carried a high risk of death from total starvation. 

For these reasons, Vince did not recommend practicing complete abstinence of food for the health and safety of his clients. 

Another issue with total fasting is that the first meal to break the fast can cause intense discomfort, such as cramping, gas, vomiting, and shortness of breath. 

Whilst many people think fasting is the perfect solution for rapid fat loss, as evidenced by a rapid reduction in scale weight, what they are actually witnessing is rapid muscle loss. Losing muscle is never desirable for the bodybuilder who has spent years slaving away in the gym, and it should be protected at all costs. 

That said, a 5-Day Fast did have its benefits, but if it was going to be done, it needed to be done in a way that would benefit the bodybuilder’s muscle-building potential, and not compromise their health or body composition in any way. 

To overcome the issues of the total fast, Vince recommended that bodybuilders continued consuming some nutrients over the course of the 5 days. 

Between days 1-3, all nutrients would be consumed in liquid form, including fruit and vegetable juices, broths, and bouillons, which would provide the body with ample vitamins and minerals required to keep the body healthy and detoxify harmful toxins. 

Light solid foods were then introduced on days 4 and 5, in order to get the bodybuilder used to eating protein once again. 

Whilst strong ‘total fasting’ advocates would be quick to dismiss this and an improper way to fast, it’s likely that they’re also not bodybuilders seeking incredible levels of muscular size and definition. Therefore, the fast must be adapted in order to make it suitable for the individual following it. One size does not fit all. 

Protein, Carbohydrates, and Fat Intake During The Fast

Since Vince did make some food recommendations during the 5-Day Fasting Diet on days 4 and 5, bodybuilders may wish to know if the care needed to be taken with regards to protein, carbohydrate, or fat (macronutrient) intake. 

However, since careful monitoring of macronutrients is only essential when the bodybuilder is seeking changes to muscle mass or body fat, bodybuilders don’t need to pay strict attention to their protein, carbohydrate, and fat intakes. Furthermore, by not having to carefully log food and beverage intake, it was one less stress for the bodybuilder to be concerned about. 

Regarding the food recommendations, the rule was to consume solid, but ‘light’ and ‘easily digestible’ foods. 

This served two benefits. 

Firstly, it didn’t stress the digestive system, which enabled it to sufficiently rest. 

Secondly, whilst it allowed the digestive system to rest, it didn’t allow it to completely ‘switch off’. This meant that when the bodybuilder returned to eating solid foods at mealtimes, it was still able to function normally, and wasn’t a shock to the body. 

This was especially important for protein digestion, since the last thing the bodybuilder wanted was to consume solid food again on day 6, but be left with undigested protein-foods putrifying in the digestive tract and triggering intense abdominal discomfort. 

5-Day Fasting Diet Example

Unlike other diets, there is no set breakfast, lunch, or dinner. 

Instead, the bodybuilder would follow a set of guidelines for each day, drinking and eating when they needed to.

Day One

Drink water, fruit, and vegetable juices only. 

Drink one tablespoon of a psyllium seed product in a glass of water, followed by a second glass of water, three times daily and before bed. 

1 x tablespoon of liquid amino acids three times daily.

Day Two

Same as day one

Day Three

Same as days one and two. 

Add clear broth or bouillon.

Day Four

Same as day three. 

Add heavier soups, Jell-O, yogurt, and custard pudding.

Day Five

Same as day four.

Add light solid foods, such as soft eggs, etc.

5-Day Fasting Diet Notes

  • Hunger will be inevitable, especially on days 1 and 2. This is perfectly normal and nothing to worry about. It’s the first stages of regaining the ‘taste’ for protein again
  • Refrain from overconsuming the permitted liquids and/or foods. The nutrients from the foods and beverages serve to maintain health and optimal body function, not to satisfy hunger
  • Managing hunger can be achieved by ensuring the bodybuilder gets sufficient sleep, reduces their stress, and refrains from being sedentary (all of these have been shown in research as effective ‘non-dietary’ means of controlling hunger and appetite levels)

Beneficial Supplements

Contrary to what many of the modern-day fasting protocols will tell you, Vince didn’t recommend any supplements during the 5-Day Fasting Diet. 

Supplements serve two purposes on Vince’s Diets: – 

  1. To accelerate changes in body composition
  2. To prevent the bodybuilder from developing a nutrient deficiency 

Once again, the 5-Day Fasting Diet was not designed for the purpose of improving body composition, nor was it long enough for bodybuilders to become deficient in nutrients. 

Furthermore, many supplements tend to be better used by the body when taken with food at mealtimes, which means that any supplements taken during the 5-Day Fasting Diet wouldn’t be used by the body optimally, and in fact, may give the digestive system unnecessary work to do. 

That being the case, Vince did recommend the use of liquid aminos, which was to help preserve muscle mass and slow down muscle loss. 

In place of liquid aminos, 10 x amino acid tablets taken three times a day would also be sufficient.

Since amino acids are what protein molecules breakdown into, these are much easier for the body to digest and do not stress the digestive system. 

Although modern-day fasting protocols are likely to recommend supplements containing nutrients to help with detoxification, a bodybuilder on the 5-Day Fasting Diet would be consuming fruit and/or vegetable juices from day 1, which would provide their body with the same nutrients. These nutrients would not only help them with detoxification, but would also enable them to maintain optimal health, function, and energy levels over the five-day fasting period. 

Complete Vegan Diet

Another diet Vince used with bodybuilders in order to rest the digestive system and reignite the taste for protein, was the Complete Vegan Diet. 

Vince noted how a diet consisting purely of vegetables was inferior for building muscle, so it’s important that the complete vegan diet was only ever followed for a short duration. 

This made it similar to the 5-Day Fasting Diet, in that it lasted a maximum of five days and consisted of a very low protein intake. 

However, the bodybuilder was free to eat unlimited quantities of raw or steamed vegetables, fruits, legumes, and whole grains. 

The increased fiber intake on the Complete Vegan Diet compared to the 5-Day Fasting Diet would have made this a more effective nutrition protocol for clearing out the digestive tract. So if the bodybuilder was struggling to build muscle, or experiencing muscle loss despite eating a lot of protein, it may have been because they weren’t able to digest it properly. The Complete Vegan Diet would clear out any waste in the digestive tract, allow it to function properly. 

Furthermore, it may have been a better option for bodybuilders who had never experienced fasting before, simply because they were able to eat solid food throughout the five days, making it easier to endure. 

Another reason for choosing the Complete Vegan Diet over the 5-Day Fasting Diet was if the bodybuilder needed to continue training. For example, if they had just competed in a bodybuilding event, and had minimal time off before the next competition, then the Complete Vegan Diet would have served as a more effective ‘bridge’ between nutrition plans than fasting, since the greater energy intake would enable them to continue training. In the event of the bodybuilder struggling to get results from their current diet, the Complete Vegan Diet could also be used for five days in order to ‘reset’ the digestive system and kickstart things again. 


Vince’s 5-Day Fasting Diet was especially for bodybuilders who had endured long periods of a high protein intake and needed to clear out their digestive tract, as well as rebuild the ‘taste’ for protein once again. 

Unlikely traditional ‘total fasting’ protocols, which had a number of unpleasant side effects, Vince recommended gradually reintroducing foods over the 5 days, as well as ensuring the bodybuilder was consuming nutrients from day 1 in order to offset any negative health concerns. 

By doing this, the bodybuilder would not only be protected against any adverse consequences to their health, but also would be better prepared for when they reintroduced solid foods into their diet post-fast. This would enable them to rapidly transition to their next diet and begin transforming their body once again, without having to take time to overcome health issues, or get used to eating solid food once again. 

When the bodybuilder needed to take a break from eating protein, but the 5-Day Fasting Diet was an inappropriate choice, due to lack of experience or the requirement to continue training, the Complete Vegan Diet was a suitable alternative. 

This was another short-term diet, but which allowed the bodybuilder to eat solid foods from day one. The increased fiber intake on this diet, may also have made it more preferable for clearing out the digestive tract, whereas the 5-Day Fasting Diet may have been better for those who simply needed a rest from eating excessive protein. 

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