Running Cadence

Recently there has been a shift in focus away from particular foot strike patterns relating to running injuries toward alterations in cadence.  While this has been a positive initiative for many runners, foot strike patterns may still have relevance in treating specific injuries.  However, altering cadence is something almost anyone can attempt and adapt to.  Shifting foot strike patterns can be more difficult.

Cadence refers to a runner’s stride rate.  Combining stride rate with stride length gives you your running speed.  It has been suggested that a cadence of 180 strides per minute is optimum.  However, in practical terms this is not relevant as cadence changes with running speed.  For example an elite runner may do an easy run at a cadence of 170 and race a 10 k with a cadence over 200.

10689830_758602744178513_8401221313807836078_nNovice runners tend to run at much lower cadences.  Coupled with lower cadences is the tendency to overstride.  Overstriding occurs when your foot contacts the ground in front of your centre of mass.  This often coincides with heel striking.

So what are the benefits of running with a higher cadence?  Research has indicated an increase in cadence can result in a decrease in force applied to the knee (patellofemoral joint) and hip when running.  Most agree this is do the foot contacting he ground beneath the body’s centre of mass.  The potential downside of this is an increase load to hamstrings and rectus femoris (quadricep) musculature.

To calculate steps/minute, count the number of times one foot strikes the ground for 30 seconds and then multiply this number by 4.  Re-test number of times in various situations.  If your cadence is consistently low (e.g., less than 160), try increasing your stride rate by 5-10%.

Remember, don’t get caught up in the absolute number relating to cadence.  If you are struggling with injury or a novice, it may be worth altering your cadence by a small percentage and see whether it helps.

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Footwear for children: Good or Bad?

The concept of ‘natural is best’ is a prominent theme at the moment and has extended to children’s footwear.

In modern times, children wear shoes from the day they start walking.  Often footwear has features such as built up heels and in some cases supportive features to control motion of the foot and ankle, affecting the function of the lower limb.  However, there are few easily accessible guidelines for parents to determine what footwear is appropriate for a child (if any) and the decision is ultimately based on information from footwear manufacturers, retailers and their shop attendants.

Advocates of natural motion recommend barefoot walking for children.  Proponents of this belief suggest there is no evidence to suggest children need or benefit from bulky footwear.  In fact, it has been suggested that healthy children with no history of injury are potentially disturbing there natural mechanics.  For example, by raising the heel (positive footwear pitch) in relation to the forefoot, some believe this will create in increased ‘tightness’ through the calf and alter ankle motion.  Over time this may result in muscoloskeletal components such as muscle, fascia and tendon adapting to this position.  Some say this is a risk factor for injury in latter years.  However, no research has ever made any such link so at this stage, it is just a theory.

However, it stands to reason that a child with no history of injury and no apparent biomechanical anomalies wear a shoe that is fairly minamilstic. Adults on the other hand, unfortunately are more complicated.  Most adults have adapted to wearing shoes with built up heels (both men and women to varying degrees in some cases) and are complicated by  factors such as degenerative changes, stiffness and injuries to name a few.  For example, a 40 year old women who has spent most of her adult life wearing a high heel shoe will often struggle to adapt to wearing ballet flats.

So should children wear shoes at all?  Simply yes.  The protective role of footwear is important and is key to limit trauma.  However, further research is required to aid the prescription of footwear over developmental milestones.  Following is guide (that is NOT based on empirical research):

– seek professional advice if you are concerned about any aspect of children’s footwear, gait or biomechanics
– for children starting to walk- use the most minimalistic footwear that allows the child as much motion as possible and proprioception (‘feel’) from the ground
– use footwear to protect children’s feet from trauma
– avoid footwear with high heel pitches  (built up heels) for all children that are healthy with no history of injury, familial history of injury, or biomechianical concern
– in cases involving growth plate injuries such as Sever’s heel, built up shoes are required (at least in the short-term) and is necessary to seek advice from a professional
– If you are concerned regarding your child’s posture/ biomechanics (e.g., flat feet) seek professional opinion