The Sciene of Base Training

By Robert Forster, Physical Therapist
This article can also be read in Triathlete Magazine January ’04 issue

Off-season is the most important season.

“Off Season” training is misconstrued by many triathletes to mean training that is somehow less important than “in season” or competitive season training. Perhaps because the early season low-intensity training is less painful, it is thought to be less important. The concept that only “hard” work produces significant gains in fitness and the greatest rewards in performance is incorrect. It may also be that Base Training benefits are not immediately obvious. A lot is happening below the skin and improvements are not readily apparent. In fact, the low-intensity off-season “Base Training” is where your most significant fitness growth will come. Impatient athletes may want to rush the early season preparation and get to the “hard stuff” too soon. Developing fitness is a recipe where adding intensity too early will ruin the final product. In fact, to the extent you develop Base Fitness in the early season will dictate the extent of your peak fitness later. Like a pyramid-shaped building where the foundation needs to be broader than the upper floors the Base fitness you develop early on must be broader than the ensuing layers of fitness you apply. For these reasons it’s important for the triathlete to intellectually understand the science happening under the skin.

Most triathletes have by now been exposed to some elements of Periodization Training ideology and have incorporated these principles into their training. The Eastern European concept of breaking the training year into cycles or phases is not as foreign as it once was and triathletes now realize it’s the most effective way to train. Furthermore, most understand the importance of a preparatory phase to precede the harder work that follows. However, confusion still exists as to what needs to be accomplished in the off-season or Base Training phase of their yearly program.

Developed by Soviet Era Sports Scientists during the Cold War, Periodization Training was developed in an attempt to dominate the world of sport. Specifically designed to avoid the performance plateaus and mental burnout in communist athletes Periodization Principles were the result of controlled research techniques. In research, controlling variables is paramount and behind the Iron Curtain the Soviets were able to do so with impunity. Each country began, of course, with ethnically homogenous groups (Russians, Bulgarians, Germans, etc.) they then “centralized” their promising young athletes to isolated training facilities. Able to control diet, sleep and environment while ignoring research edicts regarding things like consent, they manipulated exercise stimulus in search of the most effective training program design. The results may have been ethically corrupt but proved to be scientifically sound. What emerged is a model of human adaptation that provides predictable outcomes when exercise is orchestrated in a scientifically rational sequence.

Research from around the world has confirmed that development of substantial physiological infrastructure must precede the hard work of the competitive phase. Without the necessary infrastructure developed through Base Training, the hard work to prepare for competition will not be as effective and in fact may not be tolerated at all but instead lead to injury or illness. Signs of inadequate Base Training include inconsistent performances, failure to achieve optimal competition body weight (fat loss or muscle gain), frequent illness or injury, chronic fatigue and poor attitude and focus. In twenty years of designing programs I have found that athletes who wish to perform well consistently, avoid injury and reach their greatest potential, must be scientific in their approach to Base Training. To achieve this There are two distinct areas of preparation to be considered - Metabolic Fitness and Structural Integrity. Metabolic fitness translates to optimal cellular physiology in all the applicable systems of internal bodily functions: cardiovascular system, pulmonary system (lungs), nervous system, endocrine system (hormonal system), and the energy production systems in the muscles themselves. Structural integrity speaks to the resiliency of the mechanical structures of the body. This includes muscles, tendons, fascia, ligaments and bone. This aspect of Base Training is the least understood and most underdeveloped in recreational and competitive age group athletes. Too often an athlete in pursuit of optimal cellular fitness is sabotaged by insufficient structural preparation. As you ramp up the intensity of training you will need a strong foundation of physiological and physical infrastructure.

The main limiting factors of metabolic fitness prove to be the circulatory system and energy production within the muscle cells themselves. (Improved heart and lung function and neurological adaptation to exercise occur more readily). Early season low-intensity workouts promote better vascularization of the muscles. By working the muscle at low-intensity (aerobic range) the blood vessels open as demand for oxygen increases. This stimulates a profusion or growth of the smallest blood vessels (called capillaries) into the working muscles. This “capillarization” is the vascular infrastructure that will be necessary later when the increased work demands of interval training taxes the working muscles and requires a more efficient system to deliver oxygen and nutrients and remove carbon dioxide and waste products. This process of vascular growth takes 8-12 weeks and requires that exercise intensity remains low.

The second metabolic adaptation necessary in Base Training is an increase of the muscle cells aerobic energy production factories called mitochondria. These small powerhouse structures use fats and oxygen to make energy while not producing fatigue causing lactic acid and waste. Again, the stimulus for growth is low-intensity exercise of increasing duration. The body will meet the demand for aerobic energy production by increasing the number of mitochondria in each muscle cell. However, any intense exercise will cause the body to meet these demands through anaerobic energy production and thwart your pursuit of aerobic efficiency.

Here lies the secret to vast improvements in performance. The aerobic machine can and should be developed to a much higher degree than most athletes are aware. Conversely, the improvements in anaerobic energy production are more limited. The challenges for athletes and coaches are determining the proper intensity of training to develop the aerobic energy system and secondly to determine when it is adequately developed. Heretofore, intensity of training was determined by simple (220 – age x 65%) and more complicated (maffetone) formulas that are really just guess work. Fortunately, we now are able to use ErgoLab Blood Lactate testing to measure exactly where lactate levels increase in the blood and therefore when energy production is primarily aerobic and at what level of exertion a more significant contribution from anaerobic energy machines occurs. Determining this LACTATE THRESHOLD is paramount in determining the proper intensity of work in the Base Training phase. Previously, VO2 testing by the expired gas method was the standard in fitness testing. However, this method requires hoses in your mouth and a nose clip on your nostrils is cumbersome and not sensitive enough to determine Lactate Threshold and therefore does not yield proper base training heart rate zones. Likewise the hand held blood lactate testing apparatus is inaccurate in the lower end of lactate measurement exactly where precise values are needed. The ErgoLab Blood Lactate utilizes a laboratory testing protocol is currently the Gold Standard in fitness testing. Imported from Europe and refined over the last eight years this proprietary technology gives accurate, reproducible data that is reliable in determining both the heart rate zones and power production levels of which you need to train to enhance your aerobic energy production capabilities. Once developed to the proper extent you will train better, have an easier time recovering and perform consistently throughout the year.

Whether you compete in sprint triathlons or the Ironman, building a monster aerobic system will serve you best. Aerobic training will develop your ability to produce more power (speed) while burning fats, which are in abundant supply, and thus sparing the limited stores of carbohydrates in your body. Higher intensity exercise (anaerobic) begins to burn precious carbohydrate and after they are gone (BONK!!) your day is over! In addition, relying on more of your power from the anaerobic energy systems results in fatigue producing lactic acid production.

These aerobic system adaptations require extended periods of low intensity exercise and can be seriously sidetracked with even an occasional bout of higher intensity work (more on specifics of building a better aerobic system in Base Training Part II next month).

Here as well what happens under the skin is crucial to athletic success. During Base Training the well-conditioned triathlete must develop physical and mechanical infrastructure to withstand the arduous task of hill work and interval training that comes later in the Periodization training phases. The forces developed in these harder workouts put great demands on joints, bones, tendons and fascia. The early season Base training must address two primary areas of structural development: Biomechanical Efficiency and Musculoskeletal Resiliency.

The three disciplines of the triathlon each require a high degree of mechanical efficiency in terms of sound technique and form. Optimal technique in the swim, bike and run affords the well-trained triathlete two advantages. First, proper technique provides the greatest economy in energy expenditure possible, i.e., movement that produces the greatest power for the lowest cost in energy. Secondly, proper technique avoids excessive stress on tendons, fascia, joints and bones.

Conversely, faulty technique wastes precious energy and overtaxes the mechanical parts of your body. Specifically, poor technique leads to early fatigue and further breakdown in the technique, which results in poor performance and puts stress on bodily structures resulting in injury. Developing proper technique in Base Training involves a sound flexibility program, weight training, and drills.

Flexibility is defined as the range of motion of bones around a joint. Bones must have the freedom of movement to be positioned just right in the sequence of sport motion we call “proper technique”. Without adequate flexibility the muscles work overtime in an attempt to attain the best position of the bones. The muscles have to work harder as they fight the limiting effects of inflexibility. This exacts a cost on energy demands which accumulates during a race and as a result fatigue sets in and performance suffers. Regular stretching will improve flexibility and promote efficiency while avoiding injury. (In addition, stretching promotes recovery).

A well-designed flexibility program addresses each of the major muscle groups in positions that promote relaxation of the muscles and associated structures and allows for ease of breathing. The target of your stretching program is the connective tissue elements of the muscular system not the fibers themselves. The red-blood rich muscle fibers are elastic and will stretch without much resistance. Surrounding each muscle fiber and wrapping the muscles into bundles is the white connective tissue, which inhibits range of motion. Additionally, connective tissue is the material of tendons, (which attach muscles to bones), and comprises ligaments, (which attach bones to bones at the joint). Connective tissue is not immediately elastic and requires the application of slow sustained stretching to lengthen. Permanent lengthening of these structures equates to good flexibility and you are therefore one step closer to good technique. (See sidebar for stretching guidelines.) Proper swimming technique requires flexibility in the rotation of the trunk, which allows the pelvis to mirror the position of shoulders as you glide through the water. If trunk flexibility is limited in rotation you will be unable to attain this alignment and increase the drag as your body cuts through the water. This costs you precious time and energy. Likewise, in good running form the knee rise to the front must be adequate so that when the leg comes down to strike the ground it’s moving backwards to paw and grip the ground. Tightness and lack of flexibility in the buttock and hamstring muscles inhibits this aspect of proper running mechanics. In bicycling, flexibility in the muscles of the pelvis and spine allow for the correct biomechanical position on the bike. Without it the hips rock back and forth with each pedal stroke and you are unable to bend forward easily into the aerodynamic position.

Done properly, strength training for the endurance athlete is in many ways the quickest way to achieve the structural goals of the Base Training Phase of triathlon training: Joint Stability and Musculoskeletal Resiliency. Using light weights and rubber band exercises which isolate the small muscles around each joint will not only help prevent injury but will directly improve performance throughout the season. If you were to do nothing more than the low-intensity strength work of early season training the payoff in developing musculoskeletal resiliency and biomechanic efficiency will benefit you all year.

Joint stability describes the blend of proper flexibility and adequate strength necessary to maintain optimal joint alignment throughout a movement. When aligned properly at the joint bones work as levers to multiply the force of muscle contraction. In the triathlon disciplines of swimming, biking, and running the proper alignment of joints will optimize performance by improving the forces you can generate in the water ,to the pedal and on the ground and whereas misalignment of joints wastes tremendous amounts of energy and causes trauma and injury.

The tendons respond to the stress of the weight training by increasing in size and strength. This adaptation is not obvious on the outside but is part of what’s happening below the surface that is so important. Likewise, the bones will become stronger through weight training as the muscle tug and stress the bones at the attachment of the tendon. Again this adaptation is critical to avoid injury later.

The Base Training weight program called the “Anatomical Adaptation Phase” must strengthen all of the often-neglected little muscles that surround joints. Typical triathlon training creates imbalances in these small stabilizing muscles throughout the training year. Base Training is where these imbalances must be corrected to avoid injury and optimize mechanics. Since these are small muscles the weights must be kept light. For example ankle, shoulder and hip exercises requires no more than 2-3 pounds weights to start. Using heavier weights will only cause the larger stronger muscles to substitute and “protect” the imbalance. Furthermore, light weights and high repetitions will stimulate strengthening of the tendons, fascia and bones while avoiding over training these structures. The result is a musculoskeletal system that is resilient to injury.

Weight training further enhances performance by training the nervous system to stimulate more efficient muscle contractions. Muscle fibers are called into action in recruitment patterns dictated by the nervous system. Weight training fast tracks improvements in this important aspect of sports performance by burning in these nerve-muscle connection patterns quicker than sport training does. In addition, efficient movement requires one muscle to relax while the opposing muscle contracts. Energy is wasted if this contraction-relaxation sequence is not seamless and smooth. Weight training facilitates this coordination by creating strong nerve impulses to the muscle which creates more coordinated muscle function and thus facilitates good form. The caveats to early season weight training includes using weights that are too heavy, working muscles to fatigue and not stretching before, during and after weight training sessions (see strength sidebar for guidelines). By exaggerating certain aspects of your sport specific drills strengthen muscles, improve nerve recruitment patterns and condition the mechanical components of your body. These drills should be done at low-intensity levels to start and only once per week until you are sure they are being tolerated. Drills require good flexibility and therefore stretching before and after is important to avoid injury. Basically, drills convert fitness you gain in the gym into functional gains in the swim, bike and run


Base Training: Flexibility and Stretching

  • Stretching improves flexibility and therefore allows for correct mechanics or technique
  • Stretching is crucial as part of your warm up to perform better and avoid injury
  • Stretching after workouts improves recovery by “wringing” waste products out of the muscles and returning them to their normal resting length


  • Before and after every workout and competition


  • Long sustained stretches 10-30 seconds in positions that relax the target muscle and allow for easy breathing
    How Hard (intensity)
  • Follow the subsiding tension principle by moving slow into the stretch position and tuning into the tension you feel in the muscle. If tic increases as you hold the same position you have over stretched and you need to back off. If it decreases you may advance the stretch slightly

How Many:

  • Stretch all muscle groups 3 repetitions

How Long:

  • Before and after workouts a 10-20 second hold is good, on the evening stretch problem areas lightly for 60 seconds each

Base Training: Strength Work


  • Increase Musculoskeletal resiliency (injury prevention)
  • Improve muscle fiber recruitment patterns to improve efficiency of muscle contractions
  • mprove relaxation of opposing muscle groups (antagonists) to improve coordination (better form)
  • Balance muscle strength around a joint to improve joint stability


  • Two to three workouts per week per body part


  • Moderate controlled movements of body part while exhaling on the lifting portion of the exercise and inhaling on the lowering portion of the exercise
  • Stop briefly at the end of each movement up and down

How Hard (intensity)

  • Use only light weights that you can perform twenty repetitions each set while avoiding lifting to exhaustion