Nutrient Timing for Optimal Performance

Increased muscle mass comes from a cycle of muscle stimulation, muscle breakdown, and muscle rebuilding. You must train hard enough to cause a degree of muscle tissue disruption. Training hard without appropriate nutrition intervention results in a more prolonged recovery and ultimately a weaker training response.

Utilizing optimal nutrient timing can minimize the effects of muscle damage and depletion, and set the stage for a faster recovery.

The book Nutrient Timing was written by scientists and is based on scientific facts. The focus was not on what to eat, but what they believed to be more important, and that was when to eat. This article is a summary of the book Nutrient Timing by John Ivey and Robert Portman.

Nutrient Timing for Optimal Performance

nutrient timing bookDuring a muscle’s 24-hour growth cycle, there are periods when the muscle is actively involved in producing energy, periods when it is recovering, and periods when it is growing. During this 24-hour period, muscles become sensitive to specific nutrients. By timing specific nutrients to your 24-hour growth cycle, you can activate your body’s natural anabolic hormones.

By giving the body specific high-quality nutritional supplements at these specific times you will optimize exercise performance, promote optimal recovery, maximizes muscle growth and increase immune response.  There are three phases of the Nutrient Timing System:

  1. The Energy Phase
  2. The Anabolic Phase
  3. The Growth Phase

For the metabolic machinery of the muscle to function at its best during each of these periods, the appropriate amounts and types of nutrients must be consumed at the appropriate times. If you are able to deliver the right nutrient mixture to the muscles at the right time, you can greatly enhance recovery from exercise and improve muscle growth, strength and power.

Hormonal Responses to Training

Before I go onto the three phases of the Nutrient Timing System, let me briefly touch on hormones. Within the body are numerous catabolic and anabolic hormones that are stimulated by exercise. Catabolic is the breaking down of and anabolic is the building up of. So, when we’re in a catabolic state our muscle fibers are breaking down, and when we’re in an anabolic state our muscles are building up. The principles of Nutrient Timing can help you maximize the effects of the anabolic hormones while minimizing the effects of catabolic hormones.

The Energy Phase

This is the phase during your workout, where the primary metabolic objective of the muscle is to release sufficient energy to drive muscle contraction. Consuming carbohydrates during exercise will prevent depletion of muscle glycogen stores which helps extend endurance, and maintains blood glucose levels which helps delay fatigue.

Research has shown that when you consume carbohydrates with protein, amino acids, and certain vitamins, you will be able to spare muscle glycogen and achieve greater muscular endurance, reduce muscle damage, and help prepare your muscle enzymes for a faster recovery following your workout.

The Anabolic Phase

The Anabolic Phase is the most critical phase of the Nutrient Timing System. This is the 45-minute window following a workout in which your muscle machinery, in the presence of the right combination of nutrients, initiates the repair of damaged muscle protein and replenishes muscle glycogen stores.

Following the workout, the muscle machinery is primarily in a catabolic mode.  However, it is primed to switch into an anabolic mode if the right nutrients are provided.

The proper ratio of carbohydrates, protein, antioxidants and electrolytes will assist in muscle, hormone release and immune system recovery.

If insulin is stimulated when you are not exercising, it can cause a conversion of carbohydrate into fat. However, in the 45 minutes after a workout, the metabolic machinery of the muscle is extremely sensitive to insulin. Insulin has been shown to drive the rebuilding, or anabolic activity, of the muscle. Nutrients consumed during this post exercise “metabolic window” are much more effective than those consumed later, when the muscle becomes insulin resistant.

Consumption of carbohydrates during this time period is important for driving muscle glycogen recovery and muscle tissue repair and synthesis. Protein consumed without carbohydrates is far less efficient during the Anabolic Phase. Special antioxidants such as Vitamins C and E and amino acids can speed muscle recovery. Strength training depletes muscle glycogen, stimulates the acute inflammatory response, increases protein breakdown, and causes muscle damage.

The Growth Phase

This phase extends from the end of the Anabolic Phase to the beginning of the next workout. The Growth phase is where the majority of strength gain and muscle mass occurs. It is the time when the muscle enzymes are involved in increasing the number of contractile proteins and the size of muscle fibers, as well as in helping the muscle fully replenish muscle glycogen depleted during the Energy Phase.

athlete angle stopDuring the Growth Phase, consumption of carbohydrate and protein is essential to maintain optimal muscle growth. We want to maintain a high anabolic state and restore muscle glycogen, repair muscle tissue damage, and synthesize new muscle. It is important to maintain a positive nitrogen balance, which can be accomplished with a healthy balanced diet consisting of small meals every 2-3 hours.

The goals of this phase are to maintain insulin sensitivity in order to continue to replenish glycogen stores and to maintain the anabolic state. Consuming a protein and carbohydrate meal within 1 – 3 hours after resistance training has a positive stimulating effect on protein synthesis.


During a muscle’s 24-hour growth cycle, it is uniquely sensitive to specific nutrient at different times. This 24-hour growth cycle is divided into 3 phases: energy, anabolic, and growth. If you deliver the right nutrient mixture to the muscles at the right time, you can improve muscle growth, strength, and power. Nutrient optimization is the shifting of muscle from a catabolic state to an anabolic state by making available key nutrients at the appropriate time.

The metabolic window is within 45 minutes of completing each workout. A delay of supplementation of more than 2 hours can significantly reduce protein synthesis and muscle glycogen replenishment. The key to optimum recovery is the hormone insulin, which controls many of the cell’s post exercise anabolic processes.

Proper post workout supplementation has the right formula to blunt catabolic hormones and stimulate anabolic hormones, increase blood flow, replenish muscle glycogen stores, initiate tissue repair, and reduce muscular inflammation. A carbohydrate/protein supplement in liquid form is very effective in turning on the muscles’ anabolic machinery following a workout.

—See Post Workout Supplementation