hypertrophy: growth in a muscle due to increase in the size of its cells. This is the most basic adaptation we can obtain from weight training which will increase strength and muscle size. Each time you train your muscles with an appropriate stimulus, the muscle cells begin adapting. This repair process takes place within minutes, but can also last for days and requires an appropriate stimulus and appropriate recovery. 


atrophy: loss of muscle and muscle wasting which can be caused by disease or detraining. The old adage “If you don’t move it, you lose it” still applies when it comes to muscular atrophy.


sarcopenia: muscle loss associated with ageing. This is either due to a lack of stimulus and/or a disruption in the repair system that supplies the appropriate cells to maintain growth. 


isometric: an exercise where the muscle is contracted without lengthening or shortening. E.g. a plank or prone hold is an isometric exercise. Isometric exercises work well for postural muscles or to focus on weak parts of a complex movement like holding a squat at the bottom of the movement.


isotonic: an exercise where the muscle is contracted through a range, both lengthening and shortening. This is true for most normal muscular actions. E.g. seated row, bench press, bicep curl. Isotonic exercises are the easiest and most common exercises used for the major skeletal muscles. Having a controlled tempo is important and it is important to focus on both the concentric and eccentric phases of the movement. 


isokinetic: an exercise where the muscle is undertaking a constant rate of contraction and movement. This usually involves complicated equipment that is able to adjust the weight training load to control the speed of contraction of the muscle. It is rarely used due to the lack of availability of the equipment.


concentric phase: the portion of an exercise where the major muscle group is shortening. E.g. the lifting section of a bicep curl. In most exercises it is recommended to breathe out during this phase. Most people assume that this is the most important part of an exercise as it feels good to lift something and this is generally the hardest part of an exercise however it is equally important to strengthen the muscle through the opposing movement (eccentric) to stimulate as many muscle fibres as possible which can lead to increased growth and further muscle cell responses.


eccentric phase: the portion of an exercise where the major muscle group is lengthening. E.g. the lowering section of a bicep curl. In most exercises it is recommended to breathe in during this phase. There is strong evidence to suggest that it is the eccentric phase of an exercise that causes the most muscle damage and this has a strong link to DOMS (Delayed Onset Muscle Soreness). Previously DOMS was more strongly linked to a build up of lactic acid but the science has shifted on this in recent years. Anyone who has run downhill for a long period of time knows the pain this causes in the quadriceps due to the eccentric damage. Similarly, exercises that place a large force through the muscle whilst it is stretching can cause high amounts of soreness. Good examples are pec flyes, leg raises and the pullover.


failure: fatiguing a muscle to the point where you are unable to complete a full repetition at the current weight. Training to failure too often is linked to poor recovery outcomes. Training to failure on occasion can help recruit more muscle fibres and stimulate a greater muscular adaptation. It is a delicate balance.


positive failure: where failure occurs on the concentric phase of an exercise. E.g you can not lift the bar from your chest to full extension in a bench press.


negative failure: where failure occurs on the eccentric phase of an exercise. E.g. you cannot lower the bar from full extension to your chest with control in a bench press movement. This form of failure is more rarely accomplished as it requires an experienced ‘spotter’ who can judge your limits exactly. It also has increased risk as often positive failure has already been achieved. For this reason, it is rarely used but it is still a very effective technique when used properly.


mitochondria: the ‘battery’ or energy production centre of a cell. Trained muscles have an increase in mitochondria and therefore greater energy output capabilities. This is why exercising actually increases your energy levels long term, rather than depleting them. 


Delayed Onset Muscle Soreness (DOMS): the soreness associated with exercise that occurs 24-72 hours after the exercise bout. DOMS generally decreases when conditioning is improved and the training load is appropriate. It is a myth that higher levels of soreness cause greater training gains. The issuer is far more complicated than that.


The goal of all weight training is either to increase strength or to increase the look of a muscle (we can’t discount that many people train for vanity or for beauty, not performance). You could also add a third element to this which is to improve co-ordination, technique and form. This requires a more in depth application and training of the neuromuscular (nerve and muscle) system.


For the purpose of today’s blog the take home message is this: there are many ways to improve your strength but only one way that this will occur. You need to apply a stimulus that elicits the muscle to grow and provide adequate nutrition and recovery for the growth to take place.