The Renaissance Diet 2.0. Mike Israetel
the nutritional hierarchy. Fortunately, hydration levels for best performance and body composition are very similar to those needed for health; most people fulfill these requirements intuitively. In other words, drinking when you are thirsty will hydrate you adequately for health and get you very close to your best fitness hydration needs. The degree of muscle gain or fat loss anyone attains on a diet has almost nothing to do with how hydrated they are (outside of extreme circumstances). Performance can be affected by inappropriate hydration, but the effects are only substantial with more extreme or consistent dehydration or hyperhydration.
Supplements share the 5% improvement margin with hydration because they have a similarly small effect on fitness outcomes. Many available supplements have no effect at all, and even the most effective ones have been shown to have an extremely small impact on performance and body composition. Using the verified supplement options appropriately can give you an edge that may absolutely add up to a significant difference in the long term (even a less than 1% improvement on each diet phase can lead to measurable differences across a decade). Because of their small effect size however, supplements should be considered only after you have thoroughly implemented the main diet principles and only if adding supplement use does not over stress you and decrease your adherence.
HYDRATION
Hydration is the degree to which the compartments of the body are supplied with water. Dehydration, euhydration, and hyperhydration are the states of having too little, normal ranges, or too much fluid in the body’s compartments, respectively. Many trainers and nutritionists unnecessarily emphasize hydration as a top priority. Performance can be very negatively impacted if an athlete is dehydrated from a water cut prior to competition or a failure to hydrate before an extremely hard workout in a very hot environment. Under normal conditions, it takes fairly extreme mistakes in hydration to negatively impact performance, and even more to affect body composition. As mentioned, most people stay in a fairly euhydrated state just by drinking to thirst.
Preventing Dehydration
If an average person is carrying water bottles around and timing and measuring their intake precisely (not to mention using the bathroom hourly), they are not making the most of their time and focus. If you get your calories, macros, and timing in order and drink when you are thirsty, meticulously measuring water intake will not get you any additional body composition results. For those competing in sport or training under circumstances where a great deal of water is lost via sweat, thinking a bit more about hydration is warranted. By the time you feel thirsty, you are already slightly dehydrated; when water will be lost across a long, intense training session or during competition in hot weather, for example, drinking when thirsty might leave you increasingly behind in your hydration. In lab settings, testing urinary specific gravity can give a precise measure of hydration, but most people do not have a refractometer lying around. For the average person who happens to train in a way that results in substantial water loss through sweat, following are some options for the assessment and maintenance of euhydration:
Consume 1.5 ml of water per calorie eaten per day
Again, this is very specific and probably only necessary if one needs to be prepared to be perfectly hydrated for performance during hard training or competition. If you take in 2,000 calories per day, this recommendation means you would consume 3,000 ml (3 liters) of water per day. To put this in perspective for our readers in the United States, this means you should get about 5 oz of fluids per 100 daily calories. This is an average recommendation for individuals training hard under isocaloric conditions. If you are training hard while cutting calories, or in extremely hot environments, you might need more fluids. Using bodyweight and urine color assessments can help dial in these values.
Monitor Urine Color
When you are euhydrated, your urine should be light yellow like lemonade. Certain circumstances can make urine color a poor indicator of hydration such as rapid intake of large amounts of fluid or alcohol consumption. The best way to use urine color to assess hydration is to consider the average color over multiple hours and days. If you consistently see dark yellow urine, you need to drink more fluids daily. In contrast, if your urine is consistently clear, you are likely overhydrating.
Track Bodyweight
If you track your bodyweight regularly and are in an isocaloric phase, bodyweight can be an especially helpful tool in assessing hydration levels. Most daily fluctuations in bodyweight are from fluid balance. If you undertake a very high volume of training during any particular day, you can assess water loss by weighing yourself before and after that training and rehydrate accordingly.
Determining Degree of Dehydration
Dehydration levels can be classified by percentage of bodyweight change from fluid loss. Reductions in performance and increases in health risks are seen as dehydration gets more extreme.
1-2% = Mild dehydrations
2-4% = Moderate dehydration
5-6% = Severe dehydration
7%+ = Extremely severe dehydration
Following are the symptoms and effects of these dehydration classifications:
Mild Dehydration
•Thirst
•Difficulty focusing
•Mild fatigue
•Small reductions in strength and athletic performance
Moderate Dehydration
•Further difficulty focusing
•Further reductions in strength and athletic performance
•Increased risk of overheating
•Decreased sweat volume
Severe Dehydration
•Cramping
•Increased respiratory rate
•Decreased cardiac output
•Chills
•Rapid pulse
•Possible heat exhaustion (weakness, nausea, dizziness)
Extremely Severe Dehydration
•Dizziness
•Muscle spasms
•Poor balance
•Fainting
•Hallucinations
•Possible heat stroke
•Extreme body temperature
•Possible loss of consciousness
•Possible shock and coma
•Possible death
Though you may have heard of weight-class athletes in MMA and other sports pushing the limits of water weight cuts, we limit our weight cut recommendations to losses of 5% total bodyweight or less due to the dangers of severe dehydration. Above 10% bodyweight loss from water death becomes a realistic risk. For those of you dieting for other sports or for more practical reasons, techniques and supplements used to cut water weight should generally be avoided.
Chapter 15 will go over safe practices for water weight cutting up to 5% bodyweight.
Hydration Protocols