Sports science is a discipline that studies the application of scientific principles and techniques with the aim of improving sporting performance, (giving athletes the sporting edge), and there are different routes that athletes can take to gain that advantage.
Strength training is vital for an athlete’s preparation for successful participation in their chosen sport. We explore what that involves – the structure and physiology of muscles, biomechanics and New Zealand research on strength training and how this has affected some athletic performances.
Why are muscles important?
On average, muscles make up about 40% of a person’s body weight1. Muscles let us move both within our bodies (like the heart pumping or stomach2 contracting) and the obvious movements that we can see (like the eyes blinking or legs running to catch the bus).
However, muscles do much more than this. They also help you to:
- maintain posture
- stabilise joints
- keep your body at the right temperature3
In fact, without your muscles, it would be impossible to do anything. Your brain may have the idea but it is the muscles of your body that carry it out. Muscles do everything from allowing you to walk to keeping your blood flowing and passing food through your digestive system4.
What does muscle look like?
Muscle5 is what we know as meat (as in steak or chops) or as the flesh of fish. Muscle is the most plentiful tissue in many animals. Take a closer look at muscle structure and muscle types.
How many muscles?
Usually we think about the muscles that we can see, like the bulging bicep muscles in our upper arms, but the human body is made up of over 630 muscles, most of which we can’t see at all.
Nature of science
Scientists make observations and develop their explanations using inference6, imagination and creativity. Often they use models to help other scientists understand their theories. A diagram is an example of an explanatory model. Diagrams demonstrate the creativity required by scientists to use their observations to develop models and to communicate their explanations to others.
Some cool muscle facts:
- The smallest muscle in the human body is the stapedius which is only 0.1 millimetre long. It is the muscle which is attached to the tiny stirrup bone7 in your ear, which sends vibrations from the eardrum to the inner ear
- The largest muscle is the gluteus maximus. It is the uppermost of the three gluteal muscles that make up the human buttocks
- The tongue is not just one muscle – it is made up of 16 different muscles
- The busiest muscles in your body are the eye muscles (that cause you to blink) and your heart muscle (that causes your heart to beat). Both contract more than 100,000 times a day!
Muscles move
Muscles and tendons combine with the bones in our body to help us move. Tendons attach muscles to bones.
Muscles can only contract and then relax – they can never push. So for every body movement there are muscles that contract to make the bones move and others that contract to pull the bones back to their original position.
Groups of muscles work together. For example when the biceps muscle contracts to flex8 (bend) the forearm, the triceps muscle relaxes. To extend (straighten) the forearm the biceps relaxes and the triceps contracts.
The energy used to power muscle contractions is adenosine triphosphate (ATP9).
Muscle performance
There are three major factors that affect how well your muscles perform: strength, power and endurance. Muscle strength can be safely measured by estimating an athlete's one repitition maximum (1RM).
Take up the challenge
Student activities include a mixture of physical challenges to test the muscles, written challenges to test the brain and models to explore muscles and forces. They provide excellent opportunities to explore the science capabilities and the nature of science.
Physical activities
- Finger marathon investigates muscle fatigue10, recovery time and statistics.
- Lateral arm raise calculates students’ one repetition maximum (1RM11).
- Measuring grip strength gathers and examines data12 about wrist strength at different angles.
Written activities
- Measuring the power output of elite athletes analyses bench press force13, velocity14 and load data.
- The heartbeat calculator spreadsheet estimates the number of heartbeats since birth.
- Investigating whole body vibration training helps students develop visual and numerical scientific literacy15.
- Startling statements is a whimsical way to introduce or conclude a teaching unit on muscles.
- Sports and physics quiz provides contextual learning by applying physics conceptual knowledge to real-life applications
Models in science
- Biceps curl models and measures the force in the biceps muscle.
- Muscle dissection uses a chicken leg to compare red and while flesh and function.
Question bank
The The sporting edge – question bank provides a list of questions on the physiology16 and the biomechanics of muscles and at strength training. The key question is how strength training can improve sporting performance. The questions support an inquiry approach.
Key terms
For explanations of key concepts, see The sporting edge – key terms.
Timeline - breaking the 4-minute mile
This timeline follows the quest to hold the world's fastest one-mile record.
- weight: Force due to gravity acting on an object, measured in newtons.
- stomach: An organ of digestion with a sac-like shape located between the oesophagus and the small intestine. It temporarily stores food, mixes and churns it with gastric juice and allows digestion of some of the protein content of food to take place.
- temperature: A measure of the degree of hotness or coldness of an object or substance. Temperature is measured with a thermometer calibrated in one or more temperature scales. Kelvin scale temperature is a measure of the average energy of the molecules of a body.
- digestive system: The group of organs that are involved in the breakdown of food in the body, which includes the stomach and intestines.
- muscle: The tissue that makes it possible for an animal to move and to maintain its posture. Muscles also make the heart beat, force blood to circulate and move food along the digestive system. The human body has more than 600 muscles.
- inference: Conclusion from facts and reasoning.
- bone: A specialised form of connective tissue. The presence of the mineral hydroxyapatite helps to give bone its strength and density.
- flex: The act of bending a joint, such as the elbow or knee.
- adenosine triphosphate (ATP): A chemical used by cells to store and transport energy.
- fatigue: Extreme tiredness.
- 1RM: 1 repetition maximum. This is a measurement of the greatest load that can be fully moved once without failure of injury.
- data: The unprocessed information we analyse to gain knowledge.
- force: A push or a pull that causes an object to change its shape, direction and/or motion.
- velocity: Speed in a particular direction.
- scientific literacy: The knowledge and understanding of science concepts and processes, which support individuals to make informed evidence-based decisions about issues that may affect them personally or have local/global impacts.
- physiology: A branch of biology that studies the functions and activities of living organisms, including all physical and biochemical processes.
