Its ironic to think that the very place we would expect to improve our health, our posture, and functional fitness is often the place where we can do the most damage. Guessed where this place is? That’s right, the local gym! Given the grim statistic that 1 in 3 of us will have back pain at some point in our lifetime, it makes sense to perhaps use at least some of our time at the gym to reduce our chances of getting it. This article therefore seeks to explain some simple ‘spine sparing’ techniques and tips, applicable to both daily life and the gym environment. Apply them today and save your spine!

Welcome to the valley of pain! Is your programme heading you into or out of the valley?

1) HEADING INTO THE VALLEY	2) HEADING AWAY FROM THE VALLEY
Contributing Factors	Contributing Factors
Poor Posture	Improved Posture
Poor Lifting Technique	Increased Activity Levels
Prolonged Seating in Static Positions	Reduction of Static Tissue Loading
Muscular Imbalances	Good Lifting Technique
Poor Recruitment Profile of Core Musculature	Improved Muscular Indurance of Anti-gravity Musculature
Repeated Cycles of Spinal Flexion	Improved Integration of Upper /Lower Extremities and Trunk
Poor Muscular Endurance of Antigravity Muscles	Improved Recruitment Profile of Core Musculature
	Improved Agonist + Antagonist length/tension relationships

1. Posture and the Forward flexion syndrome

Introduction

We live in what I call a ‘forward flexed world’. We drive, eat, work and watch telly all with flexed (‘rounded’) spines, see figure 1. It is little surprise then that one of the most common postural problems is that of thoracic kyphosis (a rounded upper back), which if often associated with forward head carriage and rounded shoulders. The spinal consequence of living in a forward flexed world is a loss of normal thoracic mobility e.g. a ‘stiff’ upper back. Loss of normal thoracic mobility can and often does have a knock on effect on all other tissues and nerves in the body, and is often the underlying cause of many injuries to the shoulder and neck. Ultimately such a posture leads to faster wear and tear of the spinal tissues and structures, facilitating degeneration and dysfunction….essentially a fast track ticket to the valley of pain! Wouldn’t it be great if the gym represented an opportunity to correct this type of posture? Sadly most training programmes often exacerbate this type of posture! Lets look at how this can happen….


figure 1

Cardiovascular training

Though I am a keen fan of cycling and would never discourage people from it, it only takes a quick glance around the gym to see some pretty lousy cycling technique! Many people sit slouched while cycling, and so just continuing the pattern of daily postural strain. See fig 2. Remember that cycling (and rowing) are dysfunctional to the body, and so whilst cycling it makes sense to minimise the effect of this dysfunction not add to it! If your going to cycle on an indoor bike then aim to be aware of how you actually sit and cycle. I suggest tilting or pivoting at the hips slightly, thus taking the weight off your spine and redistributing the weight of your torso to the arms. Try and hold a natural curve to your lower back as opposed to letting your hips ‘roll’ under you. Try to keep the chest lifted, whilst keeping the shoulder blades depressed down the back (see figure 3)

figure 2	figure 3

Strength training

How many of you are familiar with exercises like the Chest press machine and pec deck? I’m sure you would agree they are one of the most frequently used machines in gyms. Frequent training of the ‘pecs’ combined with a lack of pec stretching can lead to tightening of the pec minor. Due to the insertion of this muscle on the coracoid process of the scapula, when it becomes ‘tight’ it can cause the shoulders to internally rotate and round forward and so encouraging spinal kyphosis. Admit it, how many of you regularly stretch your pec’s after training your chest? It really is important, particularly if you already have a rounded upper back! See figure 4 for a great ways to stretch your pec minor. To add to the problem of overzealous chest training (particularly by men), is the fact that many people don’t work the antagonistic muscle groups (the scapula retractors) to the same degree of intensity or volume. A muscular imbalance between the pecs and scapula retractors is a sure fire way of adding to the of the forward flexion syndrome! A bent over wide grip row (figure 5) is a fantastic exercise for working the scapula retractors, and can help balance out the effects of chest pressing etc

figure 4	figure 5

Core training- how to head into or out of the valley of pain!

lets take a closer look at the biomechanical consequences of one of the most common core exercises performed in the gym… the abdominal crunch! When performed on the floor, the abdominal crunch only trains the rectus abdominus (the six pack muscle) through a partial range of movement. The problem here is that working a muscle through a partial range of movement over and over again is a great way to encourage adaptive shortening/tightening of a muscle. This is not a good thing, especially when you consider that the abdominal crunch specifically targets the upper ab region. You see, if the upper abs adaptively shorten and tighten due to partial R.O.M training then they slowly begin to pull and depress the sternum (chest bone).With continual training, the effect of tight upper abs on sternal depression contributes to forward flexion syndrome. Stretching the upper abdominal area after training it would therefore seem a good idea! See figure 6 for a great way to stretch upper abs. A great alternative to the floor based ab crunch is the swiss ball crunch, see figure 7. This is because it allows the user to work the abdominals from full spinal extension to full spinal flexion (e.g. a full range of spinal motion) and so prevents adaptive shortening of the tissue.

figure 6	figure 7

Much like the situation with the pecs, many people fail to address the antagonistic/opposing muscle groups of the rectus abdominus (ab muscle). As a result, constantly training abs with no work on the opposing ‘extensor’ musculature is a great way to fast track to a muscular imbalance, the very building block of poor posture. The prone cobra is a great exercise to target the thoracic extensors (see figure 8), and can help to balance out the effect of strong, dominant upper abdominals.


figure 8

Summary

Any exercise which places the spine in a position of extension as opposed to flexion can help towards reversing the forward flexion syndrome. Whether this be a stretch (e.g swiss ball spinal extension) or strength exercise (e.g prone cobra) the key is to integrate it safely into your routine and to be consistent in your application of it. Speak to your trainer to find the right exercises for you!

2. Morning exercise anyone?

 It is still common place for many to start the day with a series of stretches or bounding in an attempt to ‘loosen up’ for the day. For people with a history of back problems, and even those currently asymptomatic, it should be made clear that performing spinal flexion (bending) exercises on awakening is possibly the worst time to do such movements! On awakening, the interverterbral disc are highly hydrated (due to the osmotic flow of water into the discs overnight) and so this alters the dynamics of the whole disc. In short the annulus fibrosis (the area of the disc immediately surrounding the nucleus) is subjected to much higher pressures during bending movements, thus decreasing the safety margin of the disc to load. Given that discs lose 90% of the fluid that they have gained over night within the first hour of arising from bed, we simply suggest you avoid doing spinal flexion exercises during this first hour. Evidence to substantiate this advice stems from Snook et al., (1998) in which it was demonstrated that the conscious avoidance of forward spine flexion in the morning improved their patients back troubles.

3.Strength training or endurance training for lower back?

Increasing ‘back strength’ still remains a common objective of many rehab-orientated gym programmes, despite strength having little to do with back health. Many long term prospective studies such as that by Leino et al., (1987) demonstrated that neither isometric or dynamic back strength predicted development of low back pain over a 10 year follow up. Holmstrom and Moritz (1992) also demonstrated that it is the specific endurance properties of the lower back musculature which is a far better predictor of who will and who wont get lower back pain. So what exactly is the difference between a strength exercise and an endurance exercise for the lower back? The difference relates to the length of time at which a muscle is placed under tension e.g. a strength exercise is often completed within 40-70 second time frame, strength/endurance 100-180 seconds, and an endurance exercise is 180 seconds plus. In terms of practical application in the gym, exercises such as the horse stance (figure 9) and static lean (figure 10) are great additions to a gym programme as these specifically target the local endurance properties of the lower back extensor musculature e.g. a single set produces 100-180 seconds of muscular tension. In conclusion, strength is for athletic performance objectives and common to popular belief has very little correlation to lower back health.

figure 9	figure 10

4. Walking

Much evidence exists to suggest that brisk walking is therapeutic to the spine (McGill et al., 1999; Nutter, 1998). In contrast, slow walking or ‘mall-walking’, is often associated with exacerbation of back pain. Several mechanisms have been put forth to explain this indifference between slow and brisk walking, one of which  pertains to the arm swing. Arms swinging during brisk walking aids in the storage and then recovery of ‘elastic energy’. As a result, the need for muscle involvement on each forward step is reduced leading to reduced tissue loading of muscles around the lower back. Indeed McGill (2002) demonstrated a 10% reduction in spinal loading from arm swinging. This is particularly important in people with back pain, as tissue tolerance to loading is generally reduced. Lastly, swinging of the arms effectively counterbalances the forward movement of the lead leg, and effectively reduces the degree of rotational torque on the lower back.

So, how do you turn a therapeutic back friendly exercise into a back killer? Simple. Do what everyone does when they put the treadmill on an incline, and that’s hold onto the bars in front of them (see figure 11). This simple act completely interrupts the natural gait pattern of walking. Instead of the arms counterbalancing the swing of the leg, the rotational force creating by walking now stays in the hips/lumbar spine. This causes a marked increase in rotational torque in the lower back, with shear and rotational torque being applied through the sacroiliac junction and the lumbar spine. The lumbar segments have limited rotational ability and so walking in this style simply puts unnecessary rotational torque through this region. To compound matters further treadmill walking is often done at speed, e.g. power walking, and so further increasing the magnitude of the rotational stress. The end result? Increased wear and tear and early degenerative changes. This is not meant to happen during walking! If your going to do brisk/power walking on the treadmill, then at least do what evolution has taught us to do during walking…. Swing the arms!


figure 11

5. Sitting

Epidemiological evidence suggests an increased risk of disc herniation in those who have sedentary jobs characterised by sitting. There are various reasons for this increased risk, but mainly they can be attributed to an increase in intra-discal pressure (discussed in part 6), an increase in the strain of the posterior region of the annulus fibrosis and ligamentous ‘creep’, which describes the decrease in stiffness of ligaments around the spine that occurs with prolonged sitting (and so increasing the susceptibility of spinal tissue to damage). For many of us, sitting represents a major part of our working day and so the question arises as to what is the best way to minimise its impact? In terms of reducing the negative effect of prolonged sitting then there is categorically, unequivocally, no substitute for getting up out of the chair! Indeed a recently proposed US guideline suggests a sitting limit of 50 mins without a standing break. Ideally a rest break would consist of movement which involves simple spinal extension exercises see figure 12. Spinal extension exercises helps to relieve the stress placed on the posterior portions of the annulus fibrosis (which is the most frequent area for disc herniation) as well as centralising the nucleus of the disc, the two key negative effects of prolong sitting.


figure 12

If frequent standing and stretching is not practical, the next best bet is to frequently change your sitting position. It is common to hear advice about the single best sitting posture, which sadly doesn’t exist! The ideal sitting posture is in fact a variable one, achieved by constantly changing position. Regularly changing posture limits the degree of static loading placed on spinal tissues, as the load is constantly being migrated from one tissue to another. In context of this, a true definition of a back friendly ergonomic chair is one that facilitates easy posture changes over a variety of joint angles. Go ahead, fidget!

6.Spinal positions and Disc pressures

Figure 13 shows a variety of spinal positions and the related disc pressures, expressed as a percentage of standing disc pressures. In particular, note the position of the highlighted stickman and how this spinal position creates the highest disc pressure of all positions shown. You may ask what’s the relevance of this to the gym environment. Well, note the similarity of this spinal position to when someone is sitting on a bench and leans forward to pick up a dumb-bell. If you consider that disc pressures can rise to 240% of standing disc pressures just by sitting and leaning forward, then imagine the additional increase in disc pressures when a 20kg dumbbell is picked up! Worse still, a large proportion of the disc pressure is orientated to the posterior of the disc, and not centrally distributed as would be if the spine was in anatomical neutral. To add to this, most people lean to one side to pick up one dumbbell at a time. So now you have a rotated spine, a fully flexed lumbar spine, plus an added weight….. potential disc herniating circumstances!  If this method for picking up and putting down a weight is repeated set after set, workout after workout, then it becomes clearly evident how spinal degeneration and/or risk of disc pathologies can soon arise! Solution? Always use the top dumbbell rack between sets to lift from, or perform a squat to get the dumbbells into position.

figure 13

LUMBAR DISC PRESSURES AS A PERCENTAGE OF STANDING, IN VARIOUS POSTURES



The Lumbar Spine, An Orthopedic Challenge by Nachesmson, A.L., Spine 1:59,1976