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Sunday, 31 October 2010 16:37 Last Updated on Sunday, 31 October 2010 17:03 Written by Administrator

Whether you are preparing for a 5k race, a century or competing in a triathlon, maximizing the benefits and minimizing the costs are the foundation for a successful training plan. Exercising at intensities that are specific to your fitness level and athletic goals is the best way to get stronger, faster and remain injury free.
Carbohydrates, fatty acids and proteins are broken down in a series of chemical reactions. The Metabolic Pathway is a series of steps using oxygen and enzymes to convert these food substrates into carbon dioxide and water. The energy stored in these substrates and then released is converted to an energy form our bodies use to sustain life (ATP). During exercise, we want to optimize the amount of energy from these substrates so that the production of ATP is reflected by the demand for ATP.
Aerobic events are any activities that take more than a few minutes to complete. Endurance events are meant to increase ones stamina. An hour spinning class is an endurance test for one person while a long course triathlon is an endurance test for another. When exercise intensity is low or moderate and the duration is long, fats provide a higher percentage of the fuel to sustain the activity. Carbohydrates are the primary energy source at higher intensities and usually over a shorter period of time. The percentage of carbohydrates versus fats used during exercise is also dependent on fitness level, diet, and hormones.
Goals for Endurance Training:

Sustain a high percentage of VO2max over a specific time or distance without fatiguing.
Reduce the use of carbohydrates as a fuel source and increase the use of fat as a fuel source at all exercise intensities.
Increase VO2max - This is a function of the amount of blood pumped from the heart each minute and the amount of oxygen in the blood that is extracted by the muscle cells.

High intensity sessions that increase this upper limit and lower intensity sessions that maximize energy production are the basics of endurance training. A metabolic test that determines aerobic and anaerobic thresholds as well as VO2peak can optimize your endurance training to achieve these goals. Although adaptations to training do occur over a wide spectrum of intensities and durations, the person who finds their fitness or weight loss goals at a plateau is too often spending their training time in between the aerobic and anaerobic thresholds.
Aerobic Threshold / First Ventilatory Threshold / Fat Max Threshold:

Rating of Perceived Exertion 4-5 out of 10
Optimum utilization of fat for fuel; increases aerobic enzymes and transport of oxygen to the muscles
Low blood lactate levels

Increased myoglobin which transports and stores oxygen within the muscle
Increased capillary density to the working muscles so oxygen, glucose and fatty acids diffuse into muscle more quickly
Increased oxidation of fat, muscular stores of triglycerides and activity of enzymes that activate, transport and breakdown fatty acids
Increased oxidation of glycogen, increased muscular stores of glycogen and glycolytic enzymes
Increased size, surface and number of mitochondria which are located in the cell and where aerobic metabolism takes place
Increased aerobic capacity and hypertrophy of type 1 fibers (slow twitch) and increased glycolytic activity in type 2 fibers (fast twitch )

A strong endurance athlete is characterized by a very good cardiovascular system and a highly developed oxidative capacity in the muscles. Oxygen can be delivered, extracted and used by the muscles in much higher amounts than an untrained or poorly trained individual. In other words, while less trained individuals are tapping generously into their glycogen stores these athletes are still using fats as a fuel source along with carbohydrates but maintaining lower blood lactate levels.
Anaerobic Threshold/ Second Ventilatory Threshold/ OBLA:

Rating of Perceived Exertion 7-8 out of 10
Beyond this intensity, blood lactate and CO2 levels rising faster than heart rate and VO2; large increases in breathing rate for small increases in intensity
Energy predominantly from muscle glycogen and blood glucose

Increases anaerobic capacity and neuromuscular power
Must incorporate high intensity intervals to improve the ability to burn fat during long endurance sessions
Very high blood lactate levels

Increased ability to tolerate high amounts of blood lactate during exercise
Increased ability to buffer lactic acid and shuttle blood lactate to other tissues
Increased muscular stores of ATP

The Aerobic Threshold (AeT) is expressed by the blue vertical line. It is the lowest value of VE/VO2 that corresponds to a relatively stable VE/VC02. VE is pulmonary ventilation or the amount of air that moves in and out of the lungs each minute that is required to consume one liter of oxygen.
Since exercise intensity is low while training near the aerobic threshold, duration can be long. This increases muscular endurance, tendon and ligament strength, and the efficiency of the aerobic system. Exercise efficiency or economy means that less oxygen is required for the same activity or that the same muscle fibers produce more energy at any given rate of oxygen consumption. The amount of oxygen you needed to run easily at a 9 minute mile is now enough for you to run easily at an 8 1/2 minute mile. Endurance athletes are very efficient at using fat to provide ATP, maintaining low blood lactate levels and sparing the use of muscle glycogen even at faster running or cycling speeds.
The Anaerobic Threshold (AT) is expressed by the light green vertical line. Beyond this point, ventilation increases disproportionally to VO2 to offset excess CO2 produced as the body buffers lactic acid. Anaerobic energy production increases to supplement aerobic energy production in order to keep pace with the demand for ATP in the working muscles.
The anaerobic threshold is also referred to as the lactate or second ventilatory threshold and signifies the point where there is a sudden increase in CO2 production, ventilation, and blood lactate levels. An endurance athlete wants his/her anaerobic threshold to be at a high percentage of their VO2max. The average untrained person has an AT of 55% of their VO2max while that of a trained endurance athlete is between 80-90%. With a high AT, you can exercise at a higher intensity while delaying the fatigue, soreness and decreased power that occur with increasing levels of acidity in the muscles and lactate in the blood.

Robin Steinberg, CSCS, LMT, CPTS, HFS has been in the health and fitness field for over 18 years - first as a licensed massage therapist and then as a strength and conditioning coach. Although she focuses on working with endurance athletes, her clients include men and women of all ages and athletic goals.

Robin graduated from the State University of New York at Albany in 1987 with a degree in finance. However, after moving to South Florida in 1991, she changed career paths, earning her massage therapy license from the Florida College of Natural Health in 1993. As Robin became more involved in local triathlons, her peer athletes soon developed into a large part of her client base. Before long, she had begun to provide strength training and stretching routines to rehabilitate the injuries she was encountering during massage appointments. Training for triathlons and other distance events offered her a unique understanding of the overuse injuries commonly seen among many endurance athletes. To support her growing expertise, Robin decided to go back to school to study exercise physiology and has been testing runners and cyclists since 2003. She is a Certified Strength and Conditioning Specialist with the National Strength and Conditioning Association, as well as a Health Fitness Specialist with the American College of Sports Medicine.

Robin's personal goal is to inspire everyone she meets to start and maintain a healthy and active lifestyle.

A VO2 Fitness Test uses a metabolic cart (CardioCoach CO2 by Korr Medical) to measure oxygen consumption, carbon dioxide production, and heart rate as intensity increases during a graded exercise test. Heart rates corresponding to the aerobic and anaerobic thresholds as well as peak VO2 are accurately determined for each individual. Relying on age based or maximum heart rate formulas to determine pacing, power, or training zones will often leave an individual training too hard on their easy days and too easy on their hard days. Calories burned at all exercise intensities based on oxygen consumption instead of preprogrammed formulas are also provided. This information alone can be the key to better endurance performance.
Metabolic tests can be performed on a treadmill, spinning bike or trainer using a triathlon or road bike. Allow 2 hours for testing.
A Resting Metabolic Rate Test determines the amount of calories needed to maintain the body's vital functions at rest. Each person's resting metabolic rate is based on genetics, eating habits, and fitness level. Knowing ones RMR is the first step towards balancing daily caloric intake with caloric expenditure. An RMR test can sometimes be the deciding factor for endurance athletes, especially women, who may not consume enough calories to fuel their endurance training and maintain or increase muscle tissue. A resting metabolic rate test can help anyone achieve their training or weight loss goals. Allow 1:15 for testing.
Personal Training: 60-90 minute sessions designed specifically for runners and cyclists. Goals include preventing overuse injuries; increasing running efficiency and power production with drills and plyometrics; building overall body and core strength; and teaching proper stretching.