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Genetic Potential In Fitness Training

Avatar for Hadyn Luke Hadyn Luke posted this on Thursday 28th of June 2012 Hadyn Luke 28/06/2012


Genetic Potential In Fitness Training

Our blog for the fitness industry this week covers how genetics can influence weight training or cardio-vascular activities.

Airbrushed celebrities v real-life fitness potential

Many personal trainers find that their clients have an image of how they want to look; often it’s an unrealistic image based on airbrushed celebrities.

Every individual’s ability to perform at a particular component of fitness can be affected by their genetics and sometimes you have to accept what you’re built for, whether you are strong in a particular area or more of a general all-rounder.

There are lots of physiological systems that influence how good you can be at the different components of fitness. These include how tall someone is in relation to the length of their limbs, the size of their heart and lungs, and the muscle fibres and fat cells they hold.

The genetics of flexibility

A personal trainer can work on a client’s flexibility, but some people will always have the genetic advantage, based on their muscle spindles, GTOs and the tightness of their ligaments.

Genetically women tend to be more flexible, because of the higher levels of the hormone relaxin in their bodies, but there are also hereditary elements to flexibility.

Those born with hypermobility within their joints have longer ligaments than normal, allowing them a greater range of movement in a joint before the tension builds on the connecting tissues. Ligaments guide the way a joint moves and prevent excessive movement. If an individual’s ligaments are longer or more flexible than the average person’s, this can create hypermobility in the joint. Although this can benefit a gymnast or contortionist, it can also result in frequently dislocated fingers, shoulders or elbows.

The impact of genetics on cardio-vascular fitness 

When a fitness instructor or personal trainer is devising a cardio-vascular training programme for a client, they will expect each individual’s capacity for training to be impacted by their genes.

Lung size, for example, will affect the amount of oxygen a client can take in during training and the size of their heart will affect the amount of blood they can pump per beat. Although both can be trained by a fitness instructor, our genetics influence the extent of what the training can achieve.

The more alveoli and capillaries within the lungs, the better a client is likely to respond to a fitness instructor’s cardio-vascular training programme. Other genetic factors include the quantity of capillaries and myoglobin in the muscles and the levels of myoglobin, haemoglobin and red blood cells in the blood stream.

A personal trainer will also find that the aerobic fitness of their clients is influenced by the amount of slow-twitch muscle fibres they have, as well as the amount and size of the mitochondria within those muscle fibres. Mitochondria are power plant cells: glucose, oxygen and fat goes in one end and energy is produced out of the other. The more mitochondria you have, the more glucose, oxygen and fat you can process, and this increased energy will allow you to run or train faster, or to maintain a high speed for longer.

A top athlete is likely to have a high number of slow-twitch muscle fibres with lots of mitochondria, plenty of myoglobin, a big heart and lung capacity, lots of capillaries and red blood cells, and other genetic advantages.

In some sporting disciplines such as long-distance running or football, an athlete with a leaner physique has the advantage over one carrying a lot of muscle tissue. Many top footballers, such as Ronaldo, may look muscular but they are actually slight and lean muscled.

Continue the discussion on our latest fitness blog below!

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