Assessing Your Fitness to Dive
Posted by Kevin in Scuba Diving on August 31, 2010
Diving normally doesn’t take a lot of energy or physical exhertion, however there are times when you may need to swim through strong currents, dive in very cold water or assist another diver. When those situations arise, you need to be sure that your level of fitness will meet the demands of the situation.
A recent research study conducted by DAN showed that 26 percent of all diving fatalities over a 10-year period were caused by cardiac events. In a separate study, 48 percent of the divers who died over a three year period were found to have a body mass index (BMI) greater than 30. If you didn’t know, a healthy BMI is between 19 and 24….so 30 places a person in the obese range.
Your BMI is only one factor in assessing your overall fitness level. A stress test conducted in an exercise lab is the most accurate way to assess your fitness level, however that is rarely available to the average person. An alternative to a full stress test is to calculate your overall fitness level by determining your exercise capacity. You can obatin that type of measurement by calculating a Metabolic Equivalent of Task or MET.
MET or the standard metabolic equivalent is a unit used to estimate the amount of oxygen used by the body during physical activity. 1 MET = the energy (oxygen) used by the body at rest, while sitting quietly or reading a book, for example. The harder your body works during the activity, the more oxygen is consumed and the higher the MET level.
Many physicians believe the ability to achieve a rating of 10 METs is adequate for the average diver.
So how does one calculate their MET or METmax value? The University of Houston created a tool called the University of Houston Non-Exercise Test for Predicting VO2max. This tool can help you determine your exercise capacity by estimating your level of physical activity and comparing it to your age and your body mass index. You can use this tool to calculate your VO2max, which can then be used to determine your METmax.
Ensuring that you are fit and able to handle the demands of your planned dives improves the safety of the dives. A secondary benefit is that you will likely use less air, therefore being able to extend your bottom time.
You can download a copy of the tool from here.
Scuba Equipment
Posted by Kevin in Scuba Diving on August 31, 2010
When you first start diving, one of the first questions you will likely have have is…."What equipment do I need to buy?" or "What equipment should I buy first?". While there’s no single answer to those questions, the answers will partially depend on how frequently and where you will be diving.
The equipment you can, or will, purchase over time includes the following. As you start to investigate specific pieces of equipment, you will quickly realize that some of the items can be relatively expensive. Dive shops and resorts will have this equipment for rent (with the possible exception of dive computers), but as you progress as a diver, you will likey want to purchase at least a few pieces of equipment of your own. I have listed some of the major pieces of equipment below, based on priority of purchase…but this is just my personal opinion 
.
- Mask & snorkel
- Fins
- Dive Log Book
- Exposure Protection
- Dive Computer
- Regulator
- Instrumentation/Gauges
- Buoyancy Compensation Device (BCD)
- Weights
- High Pressure Compressed Gas Tank
- Knife, signaling devices, etc
Estimating Required Weighting (Scuba)
Posted by Kevin in Scuba Diving on August 31, 2010
The amount of weighting that you will need to remain neutrally buoyant will varying based on a number of factors. Water salinity (fresh vs salt), type of exposure protection and body type are just a few. As you gain experience and log additional dives in your log book, you can refer to your previous dives to begin gaining an understanding of what your typical weight requirements are based on the planned dive. Prior to gaining that level of experience, you can get a good estimate of your weighting requirements by using the following guidelines.
These guidelines assume you are diving in salt water and are of an average physical build. If you have a leaner build, you can decrease the weighting slightly, if you are heavier, you should increase it slightly.
Perception
PERCEPTION
. .. .Something To Think About. .. .
Washington, DC Metro Station on a cold January morning in 2007. The man with a violin played six Bach pieces for about 45 minutes. During that time approx. 2 thousand people went through the station, most of them on their way to work. After 3 minutes a middle aged man noticed there was a musician playing. He slowed his pace and stopped for a few seconds and then hurried to meet his schedule.
4 minutes later:
The violinist received his first dollar: a woman threw the money in the hat and, without stopping,
continued to walk.
6 minutes:
A young man leaned against the wall to listen to him, then looked at his watch and started
to walk again.
10 minutes:
A 3-year old boy stopped but his mother tugged him along hurriedly. The kid stopped to look at the violinist
again, but the mother pushed hard and the child continued to walk, turning his head all the time.. This action was repeated by several other children. Every parent, without exception, forced their children to move on quickly.
45 minutes:
The musician played continuously. Only 6 people stopped and listened for a short while. About 20 gave money but continued to walk at their normal pace. The man collected a total of $32.
1 hour:
He finished playing and silence took over. No one noticed. No one applauded, nor was there any recognition..
No one knew this, but the violinist was Joshua Bell, one of the greatest musicians in the world. He played one of the most intricate pieces ever written, with a violin worth $3.5 million dollars. Two days before Joshua Bell sold out a theater in Boston where the seats averaged $100.
This is a true story. Joshua Bell playing incognito in the metro station was organized by the Washington Post as part of a social experiment about perception, taste and people’s priorities.
The questions raised:
- In a common place environment at an inappropriate hour, do we perceive beauty?
- Do we stop to appreciate it?
- Do we recognize talent in an unexpected context?
One possible conclusion reached from this experiment could be this:
If we do not have a moment to stop and listen to one of the best musicians in the world, playing some of the finest music ever written, with one of the most beautiful instruments ever made.
How many other things are we missing?
How many special persons pass us by and we do not MAKE ANY EFFORT TO get to know
them?
Vertical Blue 2010: Record Breaking Dives
Posted by Kevin in Scuba Diving on April 27, 2010
Simply amazing….diving to 300 feet, without the use of fins, on a single breath of air!
Vertical Blue 2010: Record Breaking Dives