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Fiber Type Personalities… What’s their Preferred Fuel Source?

By Kia Bourne, RDN

3 women stretching together outside

Are you a competitive athlete involved in high school, colligate, or even professional sports? Or maybe you are an ‘Everyday Athlete’- mom or family supporter running around taking care of the day -to- day needs of your family? Either way… The environment you create for your muscles absolutely matters in how you feel or perform! Each muscle in the body has its own personality and fiber type characteristics that respond to the environment we create for it. Proper fitness training techniques and optimal fuel sources to accommodate each muscle personality, is vital in establishing peak performance and to help reduce the risk of injury. Fiber Type Personalities Introducing… Explosive “heroic” IIB fiber type. I am responsible for powerful, explosive movement (think of the sprinter out of the gate, or the pitcher at the mound getting ready to hurl the ball, the shot putter or even the powerlifter). I don’t have the make up for endurance, but my abilities are heroic (short lived but heroic) and need lots of rest for full recovery. I am not used every day (unless you are pitching anything @ 95 miles per hour every day) but I am a specialized fiber that takes time and precision to develop with proper training and adequate nutrition. Endurance “Red” fiber type. I also need time and precision in training to be fully developed but my abilities are different from that of ”heroic” IIB fiber type. I am not powerful and explosive and do not like heavy weights when training as my purpose is to operate for the long haul (the marathon, triathlon, cross- country skiing, endurance swimming, etc.). I’m called “Red” because the very effective network of capillaries matured over time, carries much needed oxygen to muscles at work. Because of this, I do not easily fatigue but still need adequate rest, good food and hydration to be at my best. “Big-ness” fiber type. Hi. I’m responsible for hypertrophy, essentially for size only as opposed to skill. I’m good for specifically one sport; bodybuilding/figure competitions. There is a price I pay for getting to this size. I am a IIB fiber which has been “stressed” resulting in swelling and cortisol release. Body building is an extreme, and anyone who decides to go in this direction should do so under the direction and guidance of a knowledgeable and experienced Certified Fitness Trainer/ Coach to help minimize devastating damage. “Intermediate” fiber type. Hi there. I’m a “moderate” personality but crucial to your everyday performance. My role is supporting you in everything you do like holding your head upright, sitting in the chair, walking and standing. Essentially all of your intermediate activities are engaged by me. Preferred Fuel Source Whether it be Explosive “heroic” IIB, Endurance “Red”, Big- ness, or Intermediate fiber type at the fore front of action, carbohydrates (carbs) are the driving force behind generating sufficient energy. Carbohydrates, protein, and fat are the three fuel sources that provide the body with energy however, carbs supply energy for cellular demands, immediately or otherwise. Carbohydrate is the only macronutrient that is stored as glycogen in the muscles and liver and can be readily used for energy. Carbohydrate is responsible for providing energy for immediate activity (generating ATP) and provides fuel for sustained aerobic events as well. In addition, protein has a harder time being absorbed without carbohydrate to help bring it across to cells, and fat is also broken down to utilize energy, but not without the assistance of carbohydrate breakdown first. Sounds pretty important right? Well, it is the fuel that muscles rely on 24/7 and essentially keeps muscles energized and happy! Support your body with the fuel it requires to stay healthy and do the important jobs asked of it each day. List of Energy- Enhancing Foods Brown or wild Rice, Quinoa, Sweet Potatoes, Sprouted Grain Pasta, Cereal, Bread, Oatmeal, Rye and Oat Wasa Crackers, rice flour wrappers and noodles, red bliss potatoes, whole grain tortillas; antioxidant rich- apples, blueberries, peaches, oranges, spinach, asparagus (not an exhaustive list). Kia M. Bourne is a Registered and Licensed Dietitian Nutritionist and Fitness Professional serving as a food and nutrition resource to individuals, athletes, fitness enthusiasts, sports teams, trainers, coaches, performing artists, community groups, and healthcare professionals.

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