By Gur Nedzvetsky, 3rd year student of Physical Education (BA).
Are your students expending enough energy during practice?
In modern times, it is usual to involve the training methodology of various sport-fields with the scientific evolution of understanding how the human body works.
While major sport fields such as American football, soccer, basketball, swimming, and many other sports use physiology experts to help build the ideal training curriculum, some arts have less opportunities to expose their practitioners and teachers to the basics of physiology. Many budo practitioners also fall into this category. One of the reasons for it is that the only factor for advancement in the martial arts ranks such as dan grades is the proficiency in the art itself, and not in topics such as physiology, education, or training methodology. Even in Japan – many senseis have academic background in physical education and this is leading to a gradual change in the perspective on how to teach martial arts in a safer and more efficient way.
As outside of Japan we live in a very different naginata environment – I took the liberty to write a basic guide about physical fitness.
Here is where I start:
- Naginata today is a recreational martial art, which strives to form a strong mental spirit along with a healthy body, trough the constant practice of the naginata techniques.
- Naginata has many elements that are parallel to different aspects of other physical activities, and therefore we should benefit from the vast scientific knowledge about the human body as it was researched in other fields, such as sports, school curriculum and military.
The goal of this series of articles will be the following:
- To present basic knowledge about different energy systems in the human body
- To make the connection between the physiology theory and practical naginata drills
- To give examples of different trainings and how they can enhance one’s ability in shiai and competition.
Before we begin it is important to note that these articles are meant only to extend your understanding about the mentioned topics – if you plan to change or adjust your trainings based on what you read here – please don’t hesitate to consult with a professional physiologist in your country, as there are many variables that I am not including in these articles but are crucial to build a healthy and safe training plan.
PART 1: ENERGY
To do anything, be it moving, breathing, and even thinking – humans use energy. We use it when we are asleep when we are awake – 24/7. The more difficult is the task – the more energy will be used.
There are 2 major energy types in our body:
- Potential energy – chemical. We measure it by calories. 1 calorie = the level of heat needed to raise the heat of one Liter of water by one degree of Celsius.
- Kinetic energy – mechanic. Measured by mass, distance and time.
Work (W) = the distance(meters) a specific mass (kg) passes.
Power (P) = Work(W) that is being done in a given time (minutes)
Even when we are resting, our body still works – produces and consumes energy. And one of the best sources for energy is the oxygen we breathe. However – we need to always remember that breathing also requires energy. Specifically – burning one Liter of oxygen in our body is worth 5 calories. Breathe and use 10 Liters of oxygen = spend 50 calories.
The amount of oxygen we consume depends of course on several factors, such as the type of exercise we do. But if we assume that the person is at full rest (meaning that the person’s digestive system is also at rest – and not “lying on the couch after a big meal type of rest”) – we can narrow the variables to three:
- The size of our body – larger bodies consume more energy.
- Our age – with the age our basal metabolic rate decreases.
- The distribution of fat and muscle in our body – bigger muscles require more energy.
For most healthy people – the BMR – (the energy expenditure at complete rest), is worth roughly 250 milliliter of oxygen per minute. In other words, one uses 1.25 calories per minute just by breathing.
There is a strong connection between the body weight and the amount of oxygen we use per minute.
Let’s look at this chart. As you can see – there is a linear connection between the relative use of oxygen per 1 minute of moderate walking (without changing the tempo) and the body weight.
Example: A person who weights 50 kg will spend 8 calories per minute (1.6*5), 240 calories per 30 minutes. However, a person who weights 100 kg will spend 16 calories per minute (3.2*5) per minute, will use 480 calories per 30 minutes. In other words – bigger bodies produce more energy.
PRACTICAL APPLICATION IN THE DOJO
Understanding the connection between a person’s weight and the calories he burns during practice may have an impact on the way a sensei will form the structure of the training. I recommend filming a training session and then watch the video and check how much time of the training was spent on actual physical practice and not on talking, dealing with the equipment or waiting. If your students actually practice 40%-60% of the time – congratulations – you are a very efficient sensei.
Such high quality training can be reached by practicing a repetitive movement (for example happoburi / datotsu with or without a dummy) for a 10-15 minutes or more (the more the better), or a repetition sequence (for example moderate tempo uchi-kaeshi) will cause more calories burned then short period of excessive workout followed by a long period of rest. In other words – less talking, more repetitions!
In the picture – 10 years old students practice dummy strikes in the following order: (2 min medium intensity strike repetitions + 30 seconds of rest) X 8 rounds. Total: 20 minutes of practice, 16 minutes of actual work.
In the next article, we will discuss the main physiological characteristics of human body – fat related.