However, active people burn more calories than people who are not active. If you do not consume enough energy from your low protein diet and protein substitutes, then the body breaks down its fat and protein stores from the muscles to use for energy. This breakdown of protein releases phe into the blood causing phe levels to increase. The type, intensity and length of time exercising will determine how much energy and protein you require. Taking your protein substitute as prescribed should provide your body with enough protein.
You might want to consider the timings of your protein substitute , if you exercise on a regular basis or compete in sports. Your protein substitute contain the building blocks for muscle and it might be favourable to take this following an intense gym session, endurance event or a match. Combining your protein substitute with a carbohydrate dense meal such as rice or pasta based using your low protein foods can aid recovery.
Protein powders that some people use to increase muscle mass are not appropriate for a person with PKU as they will increase blood phe levels. If you compete competitively, your protein and energy (calorie) demands might be higher than the average person. Your metabolic team can help you to ensure you are eating enough food for your energy demands and meeting your protein needs from diet and your protein substitute, to help you achieve your activity goals, whilst staying on top of your phe levels.
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