Glossary: Evoke Endurance Terminology

• 1RM: See One Rep Max.

A

• ADENOSINE TRIPHOSPHATE (ATP): A molecule that acts as an energy-transfer medium within each cell. It is one of the end products of cellular metabolism. ATP supplies the energy for muscle contractions when its chemical bonds are broken. ATP is synthesized using the energy released when the macro nutrients in food are metabolized. ATP is continually being broken down and remade via the metabolic processes. The rate at which ATP can be re-synthesized determines the rate of work of which the human body is capable.
• AEROBIC BASE: The physiological state in an endurance athlete brought about by extensive training at low-to-moderate intensities. This training enhances the ability of the trained muscles to produce energy aerobically and especially using fat as the primary fuel. This training makes up the vast majority of an endurance athlete’s annual training volume. It supports the higher-intensity training by allowing the athlete to recover faster from intense training and races.
• AEROBIC DEFICIENCY SYNDROME: A condition common in endurance athletes who spend too much training time doing middle- to high-intensity efforts, which causes an increased development of the anaerobic glycolytic metabolic pathway and reduced development of the basic aerobic metabolic pathway in the affected muscles. If this training state persists long enough, the athlete will see a lowering of his or her Aerobic Threshold.
• AEROBIC METABOLISM: In our usage, we are referring to the cellular respiration process that takes place within the mitochondrion and whereby the end products of the breakdown of fat, carbohydrate, and protein are combined with oxygen to produce ATP. It is the primary energy-production pathway for endurance events lasting more than about two minutes.
• AEROBIC THRESHOLD (AET): The upper-most intensity of exercise where the production of ATP begins to be dominated by glycolysis rather than by the oxidation of fats. At this point, blood lactate begins to rise above the resting level. By convention, a blood-lactate concentration of about 2mmol/L (millimole per liter) is indicative of AeT. Another marker of the aerobic threshold is the depth and pace of ventilation. When conversation can’t be maintained at a normal cadence, the First Ventilatory Threshold (VT1) has been reached. VT1 corresponds closely to the AeT. This is an important physiological marker of intensity for endurance athletes because it marks the upper level of the most important training zone to use in developing aerobic capacity, the cornerstone to all endurance activities lasting over two minutes. The marker is very trainable and will move higher as measured by both speed of movement and heart rate. Top endurance athletes can have an AeT that is within 10 percent (and less) of their lactate (or anaerobic) threshold.
• ANABOLIC: The metabolic process of combining smaller molecules into larger ones. The synthesis of protein that results in new structures within the body is an example of anabolism. Hormones that stimulate the metabolism of protein synthesis are known as anabolic steroids. Training has its effect due to the anabolic process stimulated by the training bouts themselves.
• ANAEROBIC METABOLISM: The metabolic chemical reactions that take place without oxygen as one of the reactants. In terms of exercise, it refers to the cellular respiration process that takes place outside the mitochondrion but within the muscle cell, whereby energy is produced to fuel muscle contractions without the use of oxygen. Two types of anaerobic metabolism occur. For very short (ten seconds or less) bouts of very high-intensity exercise, high-energy phosphate fuels stored in the muscle cell as ATP and creatine phosphate (CP) can be used to produce energy for muscle contraction. For longer-duration, high-intensity exercise, the breakdown of glucose through anaerobic glycolysis provides the energy for ATP synthesis. When the requirement for muscle power is greater than can be met with aerobic glycolysis, the shortfall will be made up by anaerobic glycolysis. Lactate is a byproduct of anaerobic glycolysis and can be used as a marker of intensity of exercise.
• ANAEROBIC POWER ENDURANCE: Endurance of maximal effort sustainable for less than sixty seconds. This method comprises a tiny segment of the overall volume of an endurance athlete’s annual training. However, it is useful for developing Sport-Specific Strength because it requires the recruitment of a much larger muscle mass than normal, extensive, endurance training.
• ANAEROBIC (LACTATE) THRESHOLD (LT): The lowest intensity of exercise at which the production of lactate exceeds the muscle’s ability to take up and utilize that lactate as fuel in aerobic metabolism. Above this intensity, lactate levels in the blood begin to rise. The greater the intensity above the LT, the greater the rise in blood lactate.
• AUTONOMIC NERVOUS SYSTEM: The part of the nervous system responsible for control of the bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes.

B

• BASE PERIOD: The training period wherein the athlete focuses on building work capacity in the fundamental components that make up the event being trained for.
• BIOGENESIS: The production of new organisms from existing ones. Mitochondria undergo biogenesis as the means of increasing both their size and number within the cells.
• BODY WEIGHT: The resistance to movement provided only by a person’s own body weight (such as a pull-up or a push-up).

C

• CAPACITY TRAINING: Training that improves the long-term performance potential of the athlete.
• CAPILLARY: The smallest of the body’s blood vessels. The cross section of capillaries is on the order of the size of a red blood cell. They transport the blood, along with the nutrients and oxygen that it carries, into intimate contact with the organs and muscles.
• CARBOHYDRATE: An organic compound made up only of carbon, hydrogen, and oxygen. In terms of dietary makeup, the carbohydrate group comprises mainly grains, fruits, and starches.
• CARDIAC OUTPUT: The amount of blood being pumped by the heart in one minute. It is the product of the stroke volume as measured in liters per beat and the heart rate as measured in beats per minute.
• CATABOLIC: The metabolic process of breaking larger molecules into smaller ones for the release of energy. Extensive catabolism of the body’s protein structure can have a debilitating effect.
• CATALYST: A substance that increases the rate of a chemical reaction by lowering the activation energy required for the reaction to take place. The catalyst is not consumed in the reaction. Biochemical reactions are catalyzed by enzymes.
• CIRCUIT: A strength workout where an athlete completes one set each of several exercises in quick succession before returning to the first exercise and repeating the circuit. Can be repeated multiple times with various rest periods as needed for different training effects.
• CONTINUITY: Maintaining a regular schedule of training with minimal interruption.
• CORE: Vernacular for the musculature of the torso. The core is referred to as the critical link between the shoulder girdle and the pelvis. All athletic movements involve the core in either a static, stabilizing role or in a dynamic role of transmitting motion.
• CORE STRENGTH: Strengthening of the core musculature in both its static and dynamic roles is critical for all athletes. Many exercises exist for core strengthening by either isolating the core or by directing forces generated in the limbs through the core to an opposing limb or resistance from gravity.
• CREATINE PHOSPHATE: Also known as phosphocreatine, abbreviated PCr or CP, this is a highly bio-available source of high-energy phosphate stored in skeletal muscles. The CP reserve is small, lasting only five to eight seconds of an intense effort. The CP can anaerobically donate a phosphate group to ADP to form ATP for muscular contraction. During periods of low-intensity exercise, excess ATP can be used to resynthesize CP by giving up a phosphate group to the creatine to form CP by a process known as phosphorylation. This continual give-and-take mechanism allows CP to replenish and be available for repeated bouts of high-intensity work.
• CYTOSOL: The intracellular fluid in which the various cell structures live. Glycolytic metabolism takes place in the cytosol. Aerobic metabolism takes place within the mitochondria, which in turn lie within the cytosol.

D

• DURATION: The length of time of an exercise bout or training session.

E

• ECONOMY: The energy cost of locomotion. This varies with speed and modality. For example, high running economy on the flats does not directly translate to high running economy while running steeply uphill.
• ENDURANCE: The ability to resist fatigue during exercise. For high-intensity exercise, endurance is measured in minutes, whereas in low-intensity exercise, endurance is measured in hours or even days. Duration is inversely proportional to intensity. Proper endurance training helps an athlete increase the time to fatigue at a given intensity.
• ENZYME: Biological catalysts responsible for enabling the myriad chemical reactions that sustain life. As with other catalysts, they accelerate the chemical reaction by lowering the activation energy of the reactants and are not consumed during the reaction. In some cases, they speed up the reaction by more than a million times.

F

• FAST-TWITCH (FT) FIBER: A type of muscle fiber that is on the higher power end of the fiber spectrum. These fibers contract more rapidly and with greater force than their slow-twitch relatives. They are larger in cross section, have lower mitochondrial density and lower-density capillary beds suffusing them, and rely more heavily on glycolytic metabolism for ATP production. They have less endurance than the slow-twitch fibers, but a certain class of FT fibers, called FTa, can be trained for more endurance.
• FAT (DIETARY): A diverse group of chemical compounds that are insoluble in water. Fats can be categorized as saturated, unsaturated, and trans fats. The chemical bonds in fat allow it to store almost twice the chemical energy per unit of mass than carbohydrates and protein. Because of this, fats provide a large reservoir of energy for low- to moderate-intensity exercise.
• FREQUENCY: The number of times each week that an exercise routine is completed.
• FUNCTIONAL ADAPTATION: One category of changes to the human body as a result of the recurrent systematic stress of training. The adaptations to training are categorized in two general ways: functional, which relate to the function of the various body systems; and structural, which relate to the body’s structures.

G

• GENERALIZED ADAPTATION SYNDROME (GAS): The predictable way the body responds to stress as described by Canadian-Hungarian endocrinologist Hans Selye (1907–1982).
• GLYCOLYSIS: The metabolic process that breaks down glucose (a form of sugar derived from carbohydrates) into pyruvate and ATP. Glycolysis is an anaerobic process. The end product of glycolysis, pyruvate, can enter the mitochondria and undergo further aerobic metabolism if the aerobic capacity is sufficient. Pyruvate can also be a metabolic dead end when the aerobic capacity of the muscle is insufficient. In this case, the metabolite lactate accumulates with negative consequences to endurance. Glycolysis is the primary energy supply for ATP synthesis in high-intensity exercise because glycolysis proceeds at a faster rate than the breakdown of fats.
• GRADUALNESS: Adaptation to a training stimulus takes time and occurs in small increments. Rapid increases in training load cannot be accommodated long term. A successful training plan gradually progresses the training load over weeks and months in a systematic way, avoiding large and unmanageable jumps.

H

• HEMOGLOBIN: Abbreviated Hb or Hgb, this is the oxygen-carrying molecule in red blood cells.
• HOMEOSTASIS: A stable equilibrium state in an organism. Correct training disrupts homeostasis, resulting in adaptations that allow the body to handle similar training loads better in the future.
• HYPERTROPHY: In strength training, this is the training method that induces muscle growth. The increase in muscle volume can be caused by increased sarcoplasmic volume or an increase in the contractile proteins.

I

• INDIVIDUALITY: The need to account for the individual athlete’s genetics, training history, lifestyle, etc., when designing training.
• INNERVATE: To supply with nerves.
• INSULIN: A hormone central to regulating carbohydrate and fat metabolism in the body. Insulin causes cells in the liver, skeletal muscles, and fat tissue to absorb glucose from the blood. In the liver and skeletal muscles, glucose is stored as glycogen, and in fat cells, it is stored as triglycerides.
• INTENSITY: Intensity is a measure of the rate of energy consumed by the body. Intensity determines the preferential fuel the muscles use. It also determines the kind of adaptations that will be caused by the training. Common measures of intensity include heart rate, perceived exertion, blood lactate levels, and percentage of VO2 max.
• INTERVAL TRAINING: An endurance training method whereby, within one workout, bouts of higher intensity are separated by rest intervals. This allows the athlete to handle a higher volume of high-intensity training with less fatigue than when doing a continuous high-intensity effort of the same duration.

k

• KREBS CYCLE: Also known as the citric acid cycle, this is one part of the aerobic metabolic process that takes place within a cell’s mitochondria and results in the production of ATP.

l

• LACTATE, LACTIC ACID: A chemical product of glycolytic metabolism in muscle cells. It is immediately dissociated into lactate and a hydrogen ion (H+). Lactate then has two main pathways available to it whereby it can be used as fuel: 1) It can be converted to pyruvate, which can then enter the Krebs cycle of aerobic metabolism; 2) It can be converted to glucose in the liver by the process of gluconeogenesis. The release of the hydrogen ions can have the effect of lowering the blood’s pH (or increasing its acidity). If this continues without adequate buffering, it results in a burning sensation in the muscles and a forced slowing of the pace.
• LACTATE BALANCE POINT: The point where lactate production is equal to lactate removal. This is considered the point of maximal intensity that can be maintained for a long duration of many minutes without a subsequent rise in blood lactate level. Also frequently referred to as the lactate threshold (LT), or the maximal lactate steady state (MLSS). This metabolic point has a direct relation to the time to exhaustion at VO2 max intensity and, as such, bears strongly on the endurance of an athlete. It depends largely on the ability of the active muscles to oxidize lactate. Hence, the aerobic capacity of the slow-twitch muscle fibers, along with the lactate shuttle process, is largely responsible for endurance at high-intensity levels of exercise.
• LACTATE SHUTTLE: A mechanism, identified by George Brooks, a professor of integrative biology, in the early 1980s, where lactate is moved out of the muscle cell where it is being produced and into slow-twitch muscle cells where it can enter into the aerobic metabolic pathway to be used as fuel in the synthesis of ATP. This mechanism explains the importance of the Aerobic Base in supporting high-intensity training. The greater the aerobic capacity of the ST fibers to take up and utilize lactate, the more and longer high intensity can be sustained.
• LACTATE THRESHOLD (LT) (see Anaerobic Threshold): The highest intensity at which lactate removal is matched by lactate production. Above this intesity lactate begins to accumulate rapidly. Any intesnity above the LT will be unsustainable. The higher the intensity the less time it can be sustained.
• LIPOLYSIS: The metabolic process of breaking down long-chain lipids or fatty acids into Acetyl CoA that can be used in aerobic metabolism for the synthesis of ATP.
• LOAD (WEIGHT): The amount of resistance used. For the transition period, athletes should use a load 50–75 percent of their one-rep maximum. For the max strength period, they should use a load 85–90 percent of their one-rep maximum, or enough to allow only five reps.
• LOCAL MUSCULAR ENDURANCE (see Muscular Endurance): The concept of training relatively small muscle groups for endurance without imposing a large load on the cardiovascular system. This effect is accomplished by making the muscular load high through added resistance. This causes the aerobic capabilities of the high-power muscle fibers, which are responsible for the movement, to be the limit on exercise, not the cardiovascular system’s ability to supply oxygen to those muscles. The fatigue from this sort of training will be localized to that small group of muscles alone.

M

• MACROCYCLE: From conventional sports, a period representing one complete cycle of training resulting in the preparation for a major event. In competition, this period will usually coincide with an annual cycle of training, hard competition, and the regeneration/recovery necessary before embarking on another annual cycle. It is possible to have two macrocycles in one year.
• MAXIMUM LACTATE STEADY STATE: See Lactate Threshold.
• MESOCYCLE: A period of training, usually weeks long, during which the training is targeting one or a few physiologic qualities.
• METABOLISM: In general usage, this refers to all chemical reactions that occur within an organism. Relative to sport performance, we are mainly interested in the energy production necessary to yield ATP molecules and produce muscular work.
• MICROCYCLE: A period of training that is repeated several times during a Mesocycle. Typically one week in length.
• MITOCHONDRIA: The tiny (0.5–1 micrometer) organelles within all animal cells responsible for the majority of ATP production. Due to their crucial role in cellular energy production, they are often called the powerhouse of the cell. In exercise, we are mostly interested in the mitochondria in the muscle cells, which undergo adaptation resulting from training.
• MODULATION: The variation in training load. Can indicate changes in both day-to-day and week-to-week training loads from light to heavy.
• MOTOR UNIT: A group of muscle fibers and the motor nerve that fires them.
• MUSCULAR ENDURANCE (ME): Shortened from Local Muscular Endurance (see that definition). The ability to do repeated muscular contractions of the same kind against a resistance. The muscular endurance is not limited by cardiovascular endurance but rather by localized muscular fatigue. In many athletic undertakings, such as running a VK race, the limitations of performance will be largely determined by the local muscular fatigue. As such, the maximal sustainable output, or endurance, is linked directly to the athlete’s local muscular endurance in the primary propelling muscle groups.
• MUSCLE FIBER: Also known as myocyte or muscle cell, this is an elongated multinucleus cell in human skeletal muscle tissue.
• MUSCLE FIBER CONVERSION: Muscle fibers respond directly to the training stimuli imposed upon them. Chronic training of a particular type over many months has the effect of changing the muscle fiber’s characteristics. Multi-year studies indicate that prolonged endurance training will result in improved endurance of the faster-twitch fibers within an endurance-trained muscle.

o

• ONE-REP MAX: The maximum load an athlete can lift for one repetition of an exercise movement.
• ORGANELLE: A part of the internal cell structure. In our use: Mitochondria.
• OVERREACHING: A method used to temporarily apply an excessive training load to the athlete. Can be as short as one to two days or up to a week-long training camp. Needs to be done in a controlled way when the athlete has minimal life stress. Used occasionally by high-level athletes. Must be followed by a significant recovery period.
• OVERTRAINING: A condition common in endurance athletes where training bouts are no longer followed by Supercompensation. No matter the length of the recovery window, the athlete’s performance degrades. This is a serious condition that needs dramatic intervention.

p

• PARASYMPATHETIC NERVOUS SYSTEM: The part of the involuntary nervous system that serves to slow the heart rate, increase intestinal and glandular activity, and relax the sphincter muscles. Associated with the rest and digest or vegetative states.
• PERIODIZE: A structured organization of training used in all modern sports to allow the athlete to focus time and energy on developing one or a few desired training adaptations.
• PH: The measure of the acidity or alkalinity of a substance. Used in chemistry and biology to indicate the relative acidity of a compound.
• POLARIZED TRAINING: A term used to indicate a training intensity distribution where training volume is dominated by low intensity (80 percent) and high intensity (20 percent) with relatively little moderate intensity; used predominately by elite endurance athletes. This is in contrast to a distribution of intensity that places most volume in the moderate/middle intensity, which is common with lower-level athletes.
• POWER: Equals work divided by the time to complete the work. Stated another way: The rate at which work is done. Often confused with energy or work. The crucial differentiating element of power from work or energy is the measure of time in the denominator.
• PYRUVATE: One of the end products of glycolytic metabolism that can take one of two metabolic paths: 1) entering the mitochondria and undergoing aerobic metabolism if there is sufficient aerobic capacity in the muscle cell; or 2) accumulating in the cytosol of the cell and being converted to lactate.
• RECOVERY TIME: The rest interval between sets of the same exercise or between different exercises when using a circuit or in interval training.
• REPETITION OR REP: One complete exercise movement cycle. One pull-up movement would be one rep. One two-minute running bout in an interval workout would be one rep.

s

• SET: A group of repetitions. One set can contain from one rep to many, many reps in the case of muscular endurance training.
• SLOW-TWITCH (ST) FIBER: A class of muscle fibers that have greater endurance than their fast-twitch neighbors. The slow-twitch fibers are endowed with more mitochondria, denser capillarization, and higher levels of aerobic enzymes. They are smaller in cross section and contract with less force than the fast-twitch fibers. They have a higher concentration of myoglobin, so appear more red than FT fibers.
• SPECIFICITY: Training that mimics the demands of the sport in most ways.
• SPORT-SPECIFIC STRENGTH: Training that imposes muscular loads in a sport-specific manner that are higher than those used in the actual event.
• STRENGTH TRAINING: Any one of several methods of training directed at improving the contractile qualities of the muscles.
• STROKE VOLUME: The volume of blood ejected from the heart with each contraction of the cardiac muscle. This is a highly trainable quality. Endurance training leads to an increase in stroke volume up to a point that is probably largely determined by an athlete’s genetics.
• STRUCTURAL ADAPTATION: The changes to the body’s protein structures brought about by chronic training loads.
• SUPERCOMPENSATION: The post-training period during which the parameter that was trained rises to a higher performance capacity than it had before the training.
• SYMPATHETIC NERVOUS SYSTEM: A part of the nervous system that serves to accelerate the heart rate, constrict blood vessels, and raise blood pressure. Associated with the fight-or-flight response.

t

• TAPER: To reduce the training load significantly after a training buildup to allow the body to reach a higher level of performance.
• TRAINING EFFECT: Indicates, in a qualitative way, how an athlete’s body reacts and adapts to the various forms of training stimuli.
• TRAINING LOAD: A term used to describe, in a quasi-quantitative way, the type and amount of stress imposed by a single workout or period of training: the Training Load causes the Training Effect. They both depend on the type, the intensity, and the volume of work done in a training bout.
• TRAINING STIMULUS: A bout of exercise designed and executed so as to encourage certain adaptations to occur.
• TRIGLYCERIDES: A type of fat within the blood that facilitates the transfer of energy either to or from the adipose fat stores of the body.

u

• UTILIZATION TRAINING: Training that improves the near-term performance results of the athlete. Utilization training is commonly prioritized during the buildup to the competition period or the targeted event. This training models the specific demands of the event an athlete is training for.

v

• VENTILATORY THRESHOLD: A notable shift in breathing depth and rate that indicates a change in cellular respiration, and hence metabolism. Useful as a real-time indication of the intensity of exercise. Exercise science recognizes two ventilatory thresholds: VT1, which corresponds to the Aerobic Threshold, and VT2, which corresponds to the Lactate Threshold.

• VK: A race involving an elevation gain of one vertical kilometer on steep terrain.
• VO2 MAX: The measure of the maximal aerobic power an athlete can develop. Measured by comparing the rate of inspired and expired oxygen during a multistep exercise test to voluntary exhaustion.

w

• WORK: From physics. Work equals force times the distance over which the force is applied. An example would be that a 50-pound (20kg) weight lifted 10 feet (3m) has had 500-foot pounds (60kg/m) of work done to it.