Fitness and Low Back Pain

Introduction[edit|edit source]

Low back pain(LBP) is an umbrella of conditions with 80% of adults estimated to experience LBP at some point during their life^[1]. Low back pain refers to pain between the bottom of the ribs and the buttock crease.

• A high physical fitness level, and especiallymuscle endurancein theback muscles, is associated with lower risk of back pain^[2]
• A harmful misconception is thatexerciseshould be avoided when LPB is present. Understandably, many patients are reluctant to exercise out of the fear that any exercises orstretchingwill aggravate their existing back pain. They may become reluctant to exercise and rely onmedications.^[3]
• Physical activity(PA) to increase aerobic capacity and muscularstrength, especially of the lumbar extensor muscles, is important for patients with chronic LBP in assisting them to completeactivities of daily living.^[4]

This article focuses on non specific chronic low back pain (NSCLBP) and its relations with fitness.

Fitness[edit|edit source]

Physical fitness is a set of attributes that people have or achieve. Being physically fit has been defined as the ability to carry out daily tasks with vigour and alertness, without undue fatigue and with ample energy to enjoy leisure-time pursuits and meet unforeseen emergencies^[5]

Being physically fit depends on how well a person fulfils each of the components of being healthy.When it comes to fitness, these components are^[6]:

1. Cardiorespiratory Endurance -VO2 maxper Kg of body mass^[7]
2. MuscularEndurance- Currently no Gold Standard measurement for muscular endurance
3. Muscular Strength - There are a number of ways to measure muscular strength. TheBiering-Sorenson Test.is an easy to perform test for back strength. Isokinetic Dynamometry is the gold standard re back strength but is very expensive.^[8]
4. Body Composition:- The current Gold Standard is a Four-Compartment model of measurements most commonly consisting of Mass, Total Body Volume, Total Body Water and Bone Mineral Content.^[9]
5. Flexibility——光黄金标准,如Vicon运动Tracking System^[10]

The following sections will look at each of these components individually, relating it to LBP.

Cardiorespiratory Endurance[edit|edit source]

Cardiorespiratory endurance indicates how well the body can supply fuel during physical activity via the body’s circulatory and respiratory systems.

Aerobic activities that help improve cardiorespiratory endurance are those that cause an elevated heart rate for a sustained period of time. eg swimming, brisk walking, jogging, cycling^[6]

LPB relevance

• Aerobic exercise increases thebloodflow and nutrients to the soft tissues, including those in the back, hastening the thehealingprocess.
• Thirty minutes of aerobic exercise increases the body’s production of endorphins, a natural alternative for pain relief for the body. This helps with clients pain levels and may reduce reliance on medication for pain.

• A low aerobic fitness level is associated with CLBP
• 最大耗氧量(VO2max)被发现significantly lower by 10 mL/kg in men and by 5.6 mL/kg in women with CLBP compared to men/women without.^[3]

Muscular Endurance[edit|edit source]

Fitness also includes muscular endurance, which is the ability of a muscle to continue exerting force without tiring.^[6]

• Patients with low back pain have reducedlumbar extensormuscular endurance in comparison with non-sufferers.^[11][12]SeeBiering-Sorenson Test.
• Abdominalmuscular endurance in low back pain sufferers is significantly decreased in contrast to those in the normal health population^[13]
• Lumbarfatigueas a result of low muscular endurance has been shown to reduce the person’s ability to sense the positioning of thelumbar spine. People with chronic LBP have impaired ability in controlling the position of the lumbar spine after a fatiguing task, leading tolumbar instability.^[14]
• Patients with lower back pain, have a higher percentage offast type I glycolytic fibrescompared to the slow oxidative fibres. Fast twitch fibers contract quickly but get tired quickly, rendering them less resistant to fatigue. This makes these people more susceptible to back injury. Non-LBP people have a much higher percentage of slow twitch fibers, which are best for endurance work, as they can carry out tasks without getting tired, and are present in core muscles.^[15][6]

Strength and Low Back Pain[edit|edit source]

Thecoreis the group of trunk andhipmuscles that surround the spine, abdominal viscera and hip. Core muscles are essential for proper load balance within the spine,pelvis, andkinetic chain.Core strengtheninghas a strong theoretical basis in treatment and prevention ofLBP, as well as other musculoskeletal afflictions. A reduction in core strength can lead tolumbar instability.^[3]Muscle strengthening exercises form part of the NICE treatment guidelines for Early management of persistent non-specific low back pain.

The importance of the core relate to its function ie sparing the spine from excessive load and transfer force from the lower body to the upper body and vice versa.

• Having a strong, stable core helps us to prevent injuries and allows us to perform at our best.
• In order to protect the back, ideally we want to create 360 degrees of stiffness around the spine as we move, run, jump, throw, lift objects and transfer force throughout our body.
• We do this when all of the muscles in our hips, torso and shoulders work together^[16]
• Exercises to activate the deep abdominal muscles including the superficial muscles,transversus abdominis muscleand themultifidusare important for CLBP patients^[3].

Measures of Back Strength: For information here look at Physiotherapy Assessment section ofCore Stability

Few of us will have access to a isokinetic machine to measure trunk strength, as shown in video below.

[17]

Body Composition[edit|edit source]

The body is composed of water,protein, minerals, andfat. A person can potentially maintain the same weight but radically change the ratio of each of the components that make up their body.

A two-component model ofbody compositiondivides the body into a fat component and fat-free component. Body fat (storage fat) in excess can increase susceptibility tochronic illness, health complications, and LBP. Numerous studies have been conducted highlighting the relationship between increased fat content and the likelihood/prevalence of lower back pain.

• A study conducted in 2003^[18]found that there was a moderate positive relationship betweenobesityand lower back pain, however the results were based on theBMIcalculation which does not definitively measure body fat content.
• In a study conducted by Urquhart 2011 which took into account the amount of body storage fat^[19]and it was evident that there was a relationship between obesity and lower back pain
• An increase in body weight alters spinalbiomechanicsand loading, creating excess strain to be put through certain structures eg Obesity can lead to altered body positions such as exaggerated lumbar lordosis which will cause an alteration in spinal loading mechanics.

Flexibility[edit|edit source]

Flexibilityrefers to the range of movement across a joint.

Flexibility is important because it improves the ability of thekinetic chainto work smoothly and can help prevent injuries. It is specific to each joint and depends on a number of variables, including the tightness ofligamentsandtendons.

Relevance to CLBP

• Stretching the soft tissues in the trunk and lower limb eg Back and thigh muscles and the regions ligaments and tendons. This can help to mobilise the spine, and improve the range of motion of the spine, decreasing back pain. Stretching exercises decrease the muscle stiffness as a result of changes in viscoelastic properties, due to the decreasedactin-myosincross-bridges and thereflexmuscle inhibition.^[3]
• Improved range of motion assists in the spine and related areas improves the ability to complete ADLs egliftingand bending which require trunk flexion, a complex interaction combining lumbar and hip motion^[3]. Spasmodic or shortened back muscles adversely affect the complex spinal mechanics^[20].
• Tightness in the hip flexors and hamstrings can lead to aLumbar hyperlordosis, predisposing patients to lumbar facet syndrome^[21]

Conclusions[edit|edit source]

A Systematic Review of the Effects of Exercise and Physical Activity on Non-Specific Chronic Low Back Pain concluded thus:

一般的锻炼计划,结合muscular strength, flexibility and aerobic fitness is beneficial for rehabilitation of non-specific chronic low back pain. Increasing core muscular strength can assist in supporting the lumbar spine. Improving the flexibility of the muscle-tendons and ligaments in the back increases the range of motion and assists with the patient’s functional movement. Aerobic exercise increases the blood flow and nutrients to the soft tissues in the back, improving the healing process and reducing stiffness that can result in back pain.^[3]

And remember the important message is that embarking on any regular exercise will be of benefit to an overall person’s health including reducing back pain. With exercise they will look and feel better.^[6]

References[edit|edit source]