Isotonic vs Isometric Training

Over the past two posts, you have been informed about Isotonic and Isometric Contractions. From reading those posts, you will know the difference between Isotonic and Isometric contractions. But what are the advantages and the disadvantages of them?

Advantages of Isotonic Muscle Contractions

1. Isotonic Contractions strengthen the muscles throughout the range of movement.
2. It is also easily adaptable to most sports

Disadvantages of Isotonic Muscle Contractions

1. Muscles can become sore due to the stress placed upon them.
2. Muscles gain strength at the weakest point of action which is injury.

Advantages of Isometric Muscle Contractions

1. Develops Strength, especially Static Strength.
2. Quick and easy to do anywhere.

Disadvantages of Isometric Muscle Contractions

1. Muscles gain most strength through range of movement.
2. With Isometric Contractions, blood pressure is increased due to limitation of the blood flow to the heart. It is therefore not good for those with heart problems.

Differences between both contractions in relation to baseball.

• Deep fielder throwing a ball to person on a base - Isotonic
• Batter running around bases - Isotonic
• Holding bat before receiving a pitch - Isometric
• Pitcher holding the ball in the air - Isometric

Isometric Contractions

Isometric Contractions are muscle contractions which causes the muscle length to remain the same whilst under tension. i.e. no shortening of the muscle.


Examples Include:

• Tug of war 
• Scrummaging in rugby 
• Attempting to lift an immovable object 
• Holding a weight at arm's length 
• Strength tests in competitions such as World Strongest Man e.g. holding car batteries in front of you at arms length.

Isotonic Contractions

Isotonic contractions are muscle contractions which cause the muscle to change its length as it contracts and causes movement of a body part. There are two types of Isotonic contraction:


Concentric-The most common type of muscle contraction. Muscle length shortens under tension- from "long and thin" to "short and fat". Examples include:

• Pull ups; 
• Push Ups;
• Sit Ups;
• Bicep Curls;
• Throwing a ball; 
• Swinging a bat.

Eccentric- Eccentric contractions are when the muscle gets longer under tension. Examples include:

• Football/Soccer
• Walking
• Squats

Fitness: Suppleness

What is Suppleness?

Suppleness, also known as Flexibility and Mobility is the ability to move the joints through their full range of motion. Suppleness is very important for staying healthy & avoiding injury. Suppleness it is an element of fitness that should not be ignored. It should be part of all training programmes. Suppleness is not dependent on your shape.

Suppleness is specific, for example you can be flexible in your hamstring, but not your shoulders. If our muscles are left to get tight without regular stretching we lose our suppleness. We must stretch our muscles often.

Fitness: Strength

What is Strength
From one of the previous posts: "5 Major Components of Fitness" you will learn that strength is 'the ability to apply force & overcome resistance'. It is also 'the ability of the muscles to carry out daily tasks'. Strength is generally the amount of force that can be exerted by a muscle. 

 This involves:

• maximum strength- the maximum force that can be applied by a muscle to an object;
• muscular power - the amount of force applied to something or the ability to do strength performances quickly (Speed x Strength = Power);
• muscular endurance- The ability to work for long periods of time without getting tired. 

Types of Strength

Dynamic Strength- The strength we need to keep us moving over long periods of time;

Static Strength- Strength that is applied in a Stationary Position;

Explosive Strength- Maximum strength applied in one explosive quick powerful movement;

Isotonic Contraction- Muscle contraction as the muscle is moving;

Isometric Contraction- Muscle contraction in a static or stationary position.

Fitness: Stamina

What is Stamina?
As you may know from the previous post, Stamina (also known as cardio respiratory endurance, aerobic capacity and Cardiovascular Fitness) is the ability to work for long periods of time without getting tired. It can be both Muscular Stamina or Cardiovascular Stamina).

The working muscles in the body need constant energy & waste removal. The efficiency of the heart, lungs & blood vessels when doing this affects our levels of stamina.

This is scientifically known as VO2 Max. The amount of oxygen that can be transported to and used by the working muscles during exercise.

If you have high VO2 Max. You can use more oxygen than others which means you have greater stamina, can work for longer & don’t suffer from fatigue as much as others.

Stamina and Sport

Stamina is essential in sports that last longer than a few seconds.  The longer you can work without getting tired the better your performance will be in sports such as swimming running cycling or rowing.

5 Major Components of Fitness

What is Health?

The 'state of complete mental, physical and social well-being, and not merely the absence of disease or infirmity’ .

What is Fitness?

 ‘The ability to meet the demands of the environment’

What is Exercise?

'Form of physical activity done primarily to improve one’s health and physical fitness’ 

Health Related Exercise

Exercise is any physical activity that helps to improve health and physical fitness. It is also thought to improve mental health and relieve stress. 

There are 5 major components of fitness that help us to be physically healthy:

• Cardiovascular Fitness (Stamina)- The ability to exercise the entire body for long periods of time.
• Muscular Strength-The ability to apply force & overcome resistance.
• Muscular Endurance- The ability to work for long periods of time without getting tired.
• Body Composition- The percentage of bone, fat & muscle in the body.
• Flexibility (Suppleness)- The ability to move joints through their full range of motion.