This is a basic reference with short descriptions. For more thorough definitions, we highly recommend
consulting other resources online and in print.
Scapulae that at rest are abducted in the frontal plane, protracted in the sagittal plane, and internally rotated about a vertical appearance. Gives the appearance of rounded shoulders.
a commonly used movement test to classify lumbar- rotation-extension
Part of core stability achieved through muscular co-contraction, specifically the serape effect.
Increasing range of motion through voluntary contraction.
The part of the nervous system that brings information about the body to the brain.
(Anulom-vilom pranayama, or Nadi-suddhi pranayama) Different terms used for any form of alternating unilateral nostril breathing by manually closing one of the nostrils while in a seated erect position.
Insensitivity to pain.
a ligament in the knee and is one of the tissues connecting the femur to the tibia. It keeps the tibia from moving excessively anteriorly as well as rotating medially.
the amount of lateral force at the knee joint. It’s the most direct loading mechanism of the ACL and thought to be a probable component of ACL injury.
Top of scapula tilts forward relative to the bottom
the process by which someone learns an association between two stimuli, or a behavior and a stimulus.
Receiving feedback from an extrinsic source outside of the body.
The branch of the nervous system not under conscious control, including breathing, heart rate, and digestion.
The baroreflex regulates blood pressure (BP) by controlling heart rate (HR), heart contractility, and venous/arterial resistance. Low sensitivity may identify a prognosis of a diminished capacity to adjust HR as needed whereas high sensitivity as generally seen as an indicator of cardiac health.
considered the gold standard and the most used in classifying generalized joint hypermobility (GJH) from infancy to old age. It consists of five clinical maneuvers performed bilaterally, in which a positive score in ≥4 joints indicates the presence of GJH. The higher the score, the higher the laxity.
- One point is given if palms touch the floor in a standing forward bend with legs straight.
- One point for each elbow that bends backwards
- One point for each knee that bends backwards
- One point for each thumb that touches the forearm when bent backwards
- One point for each little finger that bends backwards beyond 90 degrees.
A yoga method franchised by Bikram Choudry. It’s described as a type of hatha yoga characterized by a set series of postures and breathing exercises, performed in a room heated to a very high temperature. Standard Bikram yoga classes are 90 minutes, 105 degrees, 40% humidity and repeats a series of 26 poses.
This model recognizes that pain is multi-faceted with biological, social, and psychological influences and therefore needs to be managed with multiple modalities.
of or relating to an experiment or clinical trial in which the researchers but not the subjects know which subjects are receiving the active medication or treatment and which are not: a technique for eliminating subjective bias, as the placebo effect, from the test results.
when a learner performs a single skill over and over, with repetition being the key. Variance in training is minimized or nonexistent. The learner then moves on to practice another discrete skill in the same way.
a measurement of mineral density of bones.
A set of clinical criteria and morphological features used for diagnosing Hypermobility Syndrome (HMS) that includes a Beighton score of 4 or higher and joint pain in 4 or more joints for more than 3 months. It can also include abnormalities in the skin, marfanoid habitus and other signs of tissue laxity.
complementary alternative medicine treatment
a Brazilian martial art that incorporates elements of dance, acrobatic movements, jumps, and landings. (Similar to gymnasts, these athletes may be more susceptible to lower limb injuries due to the high impact jumps and landings.)
The activity of the vagus nerve, a key component of the parasympathetic branch of the autonomic nervous system, and its influence on heart rate.
Conditions that involve narrowed or blocked blood vessels that can lead to a heart attack, chest pain (angina) or stroke. Other heart conditions, such as those that affect the heart’s muscle, valves or rhythm, are also considered forms of heart disease. The most common type of heart disease in the United States is coronary artery disease, which affects the blood flow to the heart. Decreased blood flow can cause a heart attack.
a medical condition in which the median nerve is compressed in the wrist and can cause tingling, pain and numbness in the upper extremity. It is often a result of repetitive stress and overuse.
A direct, measurable and observable outcome. It shows that change in one variable causes a change in another variable.
Brain and spinal cord. Coordinates activity of the entire nervous system.
a condition of the nervous system that involves chronic pain. When central sensitization occurs, the nervous system goes through a process called “wind-up” and stays in a persistent state of high reactivity.
A single leg test that measures pubic displacement as a measure of pelvic stability
Recurring ankle sprains that may or may not include functional impairments. Lateral ankle sprains are very common in people who are physically active. 73% of those who have had ankle sprains may develop chronic ankle instability.
Pain that lasts longer than three months
Reviews of primary research in human health care and health policy investigating the effects of interventions for prevention, treatment, and rehabilitation; internationally recognized as the highest standard in evidence-based health care resources. (from Cochrane.org)
This is used to assess bias of certain aspects within studies.
Group of participants in a study.
An intervention that focuses more on modifying thoughts, behaviors, and beliefs in order to manage the input of pain. When it comes to pain, CBT focuses more on managing pain rather than decreasing the pain itself.
A category of interventions to be distinguished from conventional therapies or medicines. Often called alternative or integrative health or abbreviated as CAM (complementary and alternative medicines).
An exercise that emphasizes production of force while a muscle is shortening.
feedback without delay. In the moment you receive feedback and can correct right then and there.
The learning benefit that results from practicing task variants in a random practice order.
Partially reduced or completely absent passive range of motion due to any number of neurological or orthopedic conditions
A group of people in a study that do not receive the same treatment (intervention) as another group in the same study. The purpose of having a control group is to give more reliable data with which to compare results. For example, a study on the effect of yoga on cardiovascular health could have two groups, giving one group the yoga program and the other group another exercise program.
A factor that could influence the results in the study and is therefore excluded from the study.
Those that have generalized joint hypermobility (GJH) but don’t have chronic musculoskeletal complaints lasting longer than 3 months. GJH is very common in athletes, dancers, martial artists, and gymnasts. They are at more risk for musculoskeletal pain but are high functioning in performance and motor control. Poor proprioception may be present as well as other symptoms of GJH.
The ability of the osteoarticular and muscular structures to maintain or retain the position of the trunk when an external force is applied, coordinated by the motor control system. The muscles around the lumbo-pelvic area that help maintain a neutral position of the spine, which is thought to be more stable. These muscles also help generate force from the trunk to the limbs.
Isolated exercises that are said to work the deep muscles of the spine (TVA and multifidus), integrated into exercise, and then progressed into functional activity.
Suggested or implied link that may be a result of a pattern. Correlational studies establish relationships between variables but not direct cause and effect.
Aka hydrocortisone. A glucocorticoid produced by the adrenal glands that is involved in metabolic processes, immune functions, and suppressing the inflammatory response. It becomes elevated in the blood during physical or psychological stress.
A study that collects and analyzes data from a population, or a representative subset, at a specific point in time.
Substances that are secreted by cells of the immune system. They have an effect on other cells. The three cytokines they analyzed in this study were interleukin-6 (IL-6), tumour necrosis factor (TNF), and C-reactive protein (CRP). These are some of the inflammation markers that can be measured and analyzed.
an epigenetic change that has a role in regulating gene expression and is studied due its potential effects on a wide range of conditions and diseases. Methylation is part of a larger field of science – epigenetics. DNA methylation occurs when DNA expressions (not the DNA code itself) are altered by epigenetics. Factors such as nutrition, environment, experience, exercise, and aging affect methylation – whether the genes are turned “on” or “off”.
when the brain decide what to do with the sensory inputs. How to respond by sending a pain signal or ignore.
A synthetic corticosteroid, used as an anti-inflammatory.
an experimental procedure in which neither the subjects of the experiment nor the persons administering the experiment know the critical aspects of the experiment; “a double-blind procedure is used to avoid experimenter bias and placebo effects.”
(occurs when the lower extremity moves medially) is believed to increase ligamentous, tendinous, articular strain. This may lead to pain and injury to the tissue.
Breathing disorders that result in chronic breathing patterns that create dyspnea as well as other symptoms. These symptoms would be in the absence of organic respiratory disease or in excess of regular symptoms, meaning once the symptoms are controlled they still have dysfunctional breathing.
Scapula movement that is not “normal”
Difficult or labored breathing, feeling of breathlessness.
Strength training that emphasizes resisting gravity and maintaining load while the muscle is lengthening. Example: One action of the hamstring is to flex the knee. This is the concentric action of the muscle. If the lower leg resists the movement of straightening the knee, that would be the eccentric aspect of strength. During running, the hamstring eccentrically works to slow down the forward motion of the leg that is moving forward.
Strengthening the muscle as it lengthens.
The part of the nervous system that brings information from the brain to the body
A collection of heritable connective tissue disorders thought to alter the biology of collagen in the body (the most abundant protein), which can lead to multi-systemic symptoms, such as: hypermobile joints and soft, stretchy skin, easy bruising, easy wounding, poor wound healing and/or atrophic scarring.
within the Ehlers–Danlos spectrum, a similar subcategory of patients having similar clinical features as HMS but lacking a specific genetic profile.
To engage in the world through experiences felt in the body, through the body, and perceived through the body
A body image model that identifies embodying activities that enhance awareness of the experience of the body, connectedness with the body, and feelings of competency and empowerment
the amount of energy or calories the body needs in order to complete a physical task. Daily energy expenditure (TDEE) is the total number of calories you burn daily.
Estradiol is a steroid and the primary female sex hormone. ACL has a receptor for this so the estradiol has been found to affect the integrity of the ligament.
Standardized and quality controlled yoga intervention led by screened instructor in a regulated setting
An intervention that focuses on pain education, reconceptualizing pain knowledge and combining it with other modes of rehabilitation as a means of pain treatment. Foremost EP teaches that pain is a marker of perceived need to protect body tissue, and not a marker of actual tissue damag
The definition of fascia continues to evolve as more research comes out. Robert Schleip describes it as a “body wide tensional network which consists of all fibrous collagenous soft connective tissues.” The continuous network tissue holds together muscle, tendons, bones, organs, and cells. Fascia comes in a variety of densities, shapes, striations, and architectures due to all of the different tensional strains that are put on the tissue.
A push or pull that has both magnitude or direction and causes an object with mass to change its velocity.
At the end of a max inhale a person is told to breathe out as hard as they can. The volume exhaled in that 1st second is the FEV1. Usually considered with FVC as a ratio (FEV1 /FVC). With a condition like asthma (obstructive disease) it is harder to exhale a large volume in that first second so the ratio is a lower value than normal. This test is used to assess overall pulmonary function.
This is measured after a max inhale; the person exhales as hard and fast as they can.
A forest plot is a graphical representation of a meta-analysis. It is usually accompanied by a table listing references (author and date) of the studies included in the meta-analysis.
The afferent nerve ending of a sensory neuron
common with people who have chronic pain. It’s a prevalent clinical characteristic that is present in 2%–57% (that’s a huge range) of the healthy population and is dependent on age, sex, and ethnicity. Because clinicians are not as aware of GJH-related chronic pain, patients tend to search for years before being diagnosed.
Grading of Recommendations Assessment, Development and Evaluation system.This system is used to rate the overall quality of the evidence in the pooled analysis.
Brain tissue that consists of neuron cell bodies and dendrites
In physics, and in particular in biomechanics, the ground reaction force is the force exerted by the ground on a body in contact with it.
one of the most common injuries in high speed running. They have a 20-33% recurrence rate. Hamstring strains often occur in stretched positions.
The most widely practiced form of yoga in the US. A combination of asana, pranayama, and dhyana.
Bone to bone contact in the hip
increased sensitivity to pain
When generalized joint hypermobility is accompanied by pain in 4 or more joints for more than 3 months.
Chronic overbreathing due to psychological or physiological conditions.
The interaction of the hypothalamus gland, pituitary gland, and adrenal gland, and their influence on stress, digestion, the immune system, mood and emotions, and energy storage and expenditure.
of unknown etiology (cause)
a protective biological response to potentially harmful stimuli. Inflammation is a stage of the biological healing process. It becomes a problem when it becomes chronic.
Pressure in the abdominal cavity
Relying on personal internal feedback which we rely on a lot in yoga.
Contraction performed with the joint angle and muscle angle fixed. A static plank is an example of an isometric exercise.
Heavy, slow, concentric and eccentric resistance training performed at a fixed speed.
an approach to Hatha yoga that emphasizes structural alignment of the body based on the teachings of B.K.S. Iyengar. The method is progressive and postures are adapted to meet the needs of the individual. Creative use of props to adapt the pose is common.
A condition that affects one or more of the joints goes beyond its normal limits. Can be diagnosed with the Beighton score, and can also include systemic issues (central nervous system fatigue, pain, anxiety, dysautonomia, and abdominal pain). Diagnosis can be difficult because there can be laxity with no systemic issues, or conversely no laxity with systemic issues. There can be a loss of range of motion due to age or physical limitation but they may still have JHM.
A disorder of the connective tissue that can result in unstable joints, skin abnormalities, chronic pain, and fatigue. It can also include many other symptoms. The term “hypermobility” includes a an array of sub categories with a wide continuum of symptomatology. The broadest umbrella term is “hypermobility spectrum disorders”. The spectrum ranges from those who are high functioning (with the only symptom being generalized joint hypermobility), to people with so many symptoms they can be debilitated. The latter would most likely be someone diagnosed as Ehlers Danlos syndrome, hypermobility type (hEDS).
The study of describing movement and motion (acceleration, displacement, time, velocity, etc.). It does not take account for what caused the movement. It’s sometimes referred to as the geometry of motion as it more specifically studies joint positions, angles, and acceleration during movement.
The study of forces that act on mass and cause motion (torque, gravity, friction, etc.).
characterized by hip adduction and internal rotation (think knees going inwards, or knock kneed during landing or squatting).
Was founded in 1965 by Amrit Desai. It is a form of gentle yoga similar to Hatha using standard yoga poses, breathwork, meditation, and mindfulness.
A test commonly used in clinical setting to assess movement quality.
The proportion of a population that at some point in their life (up to the time of assessment) have experienced the condition. Prevalence estimates are used by epidemiologists, health care providers, government agencies, and insurers.
Parts of the brain, such as the hypothalamus, amygdala, cingulate gyrus, hippocampus, and nucleus accumbens, located deep in the brain that are responsible for motivation, emotion, learning, and memory.
A literature review is a critical analysis of previously published research on a specific topic.
When we ambulate through the world our brain stores up a cache of “movement memory” created from our previous experience as well as from observing the movement of others. This storage of movement patterns first helps us to be as efficient as possible while moving around. Secondly it helps in being prepared physically for a possibly hazardous environment. When we encounter an escalator or moving sidewalk, previously the movement experience with the escalator was filed away so we can call upon the movement strategy that we used before, not having to figure it out from scratch and keeps us from toppling over when we go on the moving surface. Studies have shown when people walk onto an escalator and it’s not moving, our body still reacts as if there is going to be movement. We automatically go to the stored movement in our brains and anticipate a moving surface making us do a bit of a shimmy before we realize that the escalator is not moving. This effect has been termed the “broken escalator paradigm”, or locomotor aftereffect (LAE).
An observational study in which data is gathered from the same subjects repeatedly over a period of time. These studies can be for extended periods of time – months, years.
A previous study by Gallagher et al. has found that under a 2-hour standing protocol of people with no history of back pain 40-60% of them will develop pain (Pain developers (PD) after the 2 hours of standing. The others are deemed non-pain developers (NPD). They found that PD’s also had a relaxation of gluteal muscles in the standing experiment.
A genetic disorder that affects the body’s connective tissue. Marfan syndrome is caused by a defect (or mutation) in the gene that tells the body how to make fibrillin-1. This mutation results in an increase in a protein called transforming growth factor beta.
The subject contracts a specific muscle or group of muscles as hard as possible. This contraction is measured, often with a handheld dynamometer.
A standardized method used to measure muscle strength where the subject is asked to isometrically contract a muscle.
(more correctly, ‘difference in means’) is a standard statistic that measures the absolute difference between the mean value in two groups in a clinical trial. It estimates the amount by which the experimental intervention changes the outcome on average compared with the control. Mean is sum divided by the count.
Sensory receptors that respond to a mechanical stimulus, such as pressure or tension.
The process describing how cells sense and respond to mechanical stimuli through conversion to biochemical signals that cause specific cellular responses.
Online databases that hold biomedical and life sciences journal citations and abstracts.
Quantitative review of research results from multiple studies to derive conclusions on the collective body of research.
A single MET is defined as the amount of oxygen a person consumes (or the energy expended) per unit of body weight during 1 minute of rest.
Clustering of metabolic changes including abdominal obesity, high triglycerides, low HDL-cholesterol, high blood pressure, and high blood sugar.
Balance evaluation systems test. This 14 task evaluation assesses 6 different areas that influence balance, stability, postural responses, sensory orientation, dynamic balance during gait and cognitive effects. Each task is scored 0 to 2 with a max score of 28. Things like standing on one leg, seeing the quality of how they fall, standing with eyes opened and closed, and the get up and go test (TUG), are some of the tasks in this evaluation.
The distance between a joint axis and the line of force acting on it. Every joint that is involved in an exercise has a moment arm. The longer the moment arm is the more load will be applied to the joint axis through leverage.
A set of processes associated with practice or experience leading to relatively permanent changes in movement capability.
A one-dimensional measurement of muscle length, such as the ability of a muscle to extend to an endpoint. Increases in muscle extensibility are here demonstrated by end-range joint angles. In stretching research in humans, most often this means a subject’s sensation.
The ability of a muscle to withstand load. It refers to how the muscle will deform in relation to the amount of force acting on it. (Biomechanically speaking, this has nothing to do with the sensation of stiff or tight muscles)
For research purposes, the contractile muscle tissue and the fibrous connective tissue cannot be separated in a living human. Therefore, when using the term ‘muscle’ in this article it means the muscle-tendon unit.
Using active and passive movements to restore and improve mobility in common postures and during extremity movements.
The ability of the brain to change its structure and function throughout the lifespan
An agent that preserves either neuron structure or function
A 16 point questionnaire with five point scale questions that assesses symptoms associated with dysfunctional breathing.
Nociceptors are sensory neurons that alert us to potential damage. They detect extremes in temperature and pressure and injury-related chemicals, and relay that information to the brain. The brain then evaluates those signals and “decides” whether or not to emit a pain signal.
Lower back pain that does not have a pathology. It does not have a diagnosis. NSLBP is sometimes defined as pain or stiffness between the bottom ribs and buttock crease, with or without leg pain. Approximately 80% of the population experiences LBP. 90% of acute episodes recover within 6 weeks.
A statement that suggests nothing interesting is happening. The researcher tries to disprove, reject or nullify this statement. The ‘null’ often refers to the common view of something, while the alternative hypothesis is what the researcher really thinks is the cause of a phenomenon.
A genetic bone disorder characterized by fragile bones that break easily. It is also known as “brittle bone disease.”
Precursor to bone loss with lower BMD than normal but not less than an osteoporosis diagnosis.
A condition of decreased bone mass with a bone mineral density T-score that ranges from -1.0 to -2.5. This leads to fragile bones which are more at risk for fractures.
The amount of load or resistance, providing a greater stress, or load, on the body than it is normally accustomed to in order to create a desired outcome such as increased strength or bone density. Progression is the way in which an individual should increase the load.
A probability value calculated from data in the study that shows strength of evidence for or against the null hypothesis.
- A small p-value (typically ≤ 0.05) indicates strong evidence against the null hypothesis, so you reject the null hypothesis.
- A large p-value (> 0.05) indicates weak evidence against the null hypothesis, so you fail to reject the null hypothesis.
- p-values very close to the cutoff (0.05) are considered to be marginal (could go either way). Always report the p-value so your readers can draw their own conclusions.
Part of core stability achieved through osseous and ligamentous structures.
Increasing range of motion through passive resistance.
Assessed like FVC but measuring the flow rate of air exhaled.
A peer reviewed article that focuses on current advances and future directions on a particular topic
A small scale preparatory study that assesses feasibility, time, cost, and effect size. Pilot studies are crucial for good study design and useful for improving upon related future studies.
The number of persons with disease in a time interval (eg, one year) divided by number of persons in the population; that is, prevalence at the beginning of an interval plus any incident cases.
Top of scapula tilts backwards relative to the bottom
Health interventions that are implemented before there is presence of a disease
Preferred Reporting Items for Systematic Reviews and Meta-analyses. This is a protocol for meta analyses papers.
Originally a rehabilitation technique developed over 50 years ago, today’s version of PNF usually involves isometrically contracting a muscle, followed by relaxing the muscle, allowing an increase in range of motion. PNF was initially used in diagonal patterns in order to lengthen the muscle group as much as possible and incorporate the stretch reflex.
A prospective study watches a cohort (a group of people with a commonality) for the development of certain outcomes over a defined study period (usually long) and attempts to establish risk factors and/or protections factors of these outcomes.
Related to social factors and individual thoughts and behaviors.
A special way of creating a stereo image of an area by taking two x-rays of the same area, at the same time
A study where the subjects are selected by chance (randomly) to participate in an intervention and compared to one or more groups of subjects, one of which participated in no intervention at all (control group).
Involves repeated observations of the same sequence of treatments over long periods of time as well as randomly assigning interventions to the subjects. It’s said that randomized studies provide high reliability and validity to statistical estimates.
In sports and particularly exercise testing, the Borg RPE Scale measures perceived exertion. In medicine this is used to document the patient’s exertion during a test, and sports coaches use the scale to assess the intensity of training and competition. The RPE scale is used to measure the perceived intensity of your exercise and runs from 0 – 10.
Non-standardized and variable yoga sequences and instruction you may encounter out in the world
The strength of the breathing muscles is assessed by inhaling (Maximum inspiratory pressure – MIP) or exhaling (maximum expiratory pressure – MEP) against an obstructed airway piece and measuring the pressure reached.
range of motion in joints
A synovial joint comprised of the sacrum and the two ilium bones
The position of the scapula at rest on the thorax
As the humerus elevates there is a corresponding upward rotation of the scapula
The functional joint formed by the scapula and the thorax. Lacks ligaments, a joint capsule, and direct osseous connections so it isn’t considered a true joint.
Lateral curve of the spine
A form of occupational therapy in which special exercises are used to strengthen the patient’s sense of touch (tactile), sense of balance (vestibular), and sense of where the body and its parts are in space (proprioceptive).
The interaction between the rhomboids, serratus, and obliques: these muscles orient diagonally, providing force production between the hip and opposite shoulder; the serape effect provides the muscles of the core an optimal length-tension environment to maximize force production.
The process used by researchers to determine whether the null hypothesis is rejected, in favor of the alternative research hypothesis, or not. The test involves comparing the observed values with theorized values.
occur in joints and ligaments.
The ability of a system to return to an orientation or movement trajectory after a perturbation
occur in tendons and muscles.
Atechnique that indirectly measures brain anatomy differences
A way to analyze muscle activity through the use of surface electrodes.
An analysis that answers a defined research question by collecting and summarizing all empirical evidence that fits pre-specified eligibility criteria.
A statistical examination commonly used to determine if the mean of a population significantly differs from a specific value (called the hypothesized mean) or from the mean of another population.
A specific type of interstitial cell that has long telopodes and a small cell body.
Tendon pain and dysfunction.
Stability of the SI joint from the muscles, ligaments, and thoracolumbar fascia that support the pelvis
The stability in the SI joint that comes from the self locking mechanisms of the pelvis; the result of the anatomy and shape of the bones that comprise the SI joint
Fascial structure that connects the lower limb via the gluteus maximus to the upper limb (via the latissimus dorsi).
Ujjayi breathing is a commonly practiced form of slow breathing coupled with a glottis muscle contraction to provide resistance in the respiratory passageway.
Inferior angle of the scapula moves upward and laterally and is often accompanied by shoulder abduction or flexion
A type of imaging that uses high frequency waves to look at structures and organs inside the body.
Also known as the tenth cranial nerve, it connects the heart, lungs and digestive tract with the brain by way of the parasympathetic nervous system. The vagus nerve can send and receive signals about bodily states.
A measurement of Oxygen intake and use. Measured in millilitres per kilogramme of body weight per minute (ml O2/kg/min).
A measurement of the highest amount of oxygen taken in and used during a maximal exertion test (usually on treadmills or cycle ergometers).
The maximum voluntary ventilation (MVV) is the max amount of air that can be inhaled and exhaled within one minute.
A measurement tool that attempts to get a value for a subjective experience like pain. With pain, a person is shown a sheet of paper with a line on it that notes minimum on one side, and max on the other and told to evaluate and mark their pain along that line.
After a max inhale, the person exhales slowly and not forcibly.
An analysis technique that utilizes complex statistics to determine brain volumes
A group of participants included in a study that is assigned to a temporary waiting list that later receives intervention after the active treatment group. It is not an active control group which would receive a placebo treatment. It is not considered to be as reliable as active control groups however it is often used in psychological studies.
Established in the 1890s by German anatomist Julius Wolff, bone grows and remodels in response to the forces that are placed upon it. After injury to bone, placing specific stress in specific directions to the bone can help it remodel and become normal healthy bone again. If gradually increase load on a particular bone over time, the bone will remodel itself over time to become stronger to resist that sort of loading.