They used to think that babies may choke due to lack of sufficient strength to turn the head. (momjunction.com)
Your centre or core should be your first priority, because without sufficient strength in this area you are vulnerable to injury. (womenshealthandfitness.com.au)
It makes sense that without sufficient strength to propel one's body on land or through water there will not be significant speed available. (blog.bridgeathletic.com)