Cardiorespiratory Basics
This is the primary form of energy currency stored in cells and released for cellular work.
Adenosine Triphosphate (ATP)
This process refers to an increase in total muscle size caused by an increase in the size and number of individual myofibrils.
hypertrophy
This term refers to the maximum amount of weight a person can lift in a single effort to assess overall muscular strength.
1-Repetition Maximum (1-RM)
This energy system provides ATP immediately for explosive movements lasting 10 seconds or less.
immediate (or ATP-CP) energy system
According to general ACSM fitness guidelines, strength training should be performed at minimum on this many nonconsecutive days per week.
2 nonconsecutive days per week
These specialized cells located in the right atrium act as the natural pacemaker of the heart.
sinoatrial (SA) node
Muscle fibers are composed of smaller protein structures called myofibrils, which contain these basic contractile units.
sarcomeres
Isometric exercises involve muscle contraction without movement, making them also known by this name.
static exercises
Also called the nonoxidative system, this anaerobic system creates ATP by breaking down glucose and glycogen for high-intensity efforts up to 2 minutes.
anaerobic energy system
This general formula estimates a person's maximum heart rate (MHR) using their age.
220−age
During exercise, this process allows oxygen to move from the lungs into the blood while carbon dioxide moves from the blood into the lungs.
diffusion
These red, fatigue-resistant muscle fibers rely primarily on aerobic energy pathways and are recruited during endurance activities.
slow-twitch muscle fibers
Dynamic exercises, which involve muscle contractions that result in joint movement, are also known by this term.
isotonic exercises
Cellular structures called powerhouses where the oxidative production of ATP takes place.
mitochondria
For a general fitness program that builds both strength and endurance, ACSM recommends performing a set of this specific repetition range for each exercise.
8 to 12 repetitions
This systemic value represents the highest rate of oxygen consumption an individual can reach during maximum exertion.
maximal oxygen consumption (VO2max)
Made up of a motor nerve connected to several muscle fibers, this structure contracts on an "all-or-none" basis when activated.
motor unit
In a dynamic movement like an arm curl, the muscle performs a concentric contraction as it shortens, followed by this type of contraction as the muscle lengthens while lowering the weight.
eccentric contraction
This energy system uses carbohydrates, fats, and occasionally proteins to produce ATP for sustained activities lasting longer than two minutes.
oxidative (or aerobic) energy system
This subjective monitoring scale ranges from 0 to 10 and lets exercisers gauge their workout intensity without counting a pulse.
Rating of Perceived Exertion (RPE) scale
These large blood vessels return waste-laden, oxygen-poor blood from the body back into the heart's right atrium.
venae cavae
These rapidly contracting muscle fibers fatigue quickly and are preferentially increased in size through high-resistance strength training.
fast-twitch muscle fibers
Statically strengthening a muscle at its weakest point in a range of motion helps overcome weak points during these types of exercises.
dynamic (or isotonic) exercises
The point during high-intensity exercise where metabolic acids abruptly accumulate in the blood faster than they can be cleared.
lactate threshold
This fitness assessment predicts maximal oxygen consumption by having a participant walk briskly for 1 mile and recording the completion time and final heart rate.
1-Mile Walk Test