Tuesday, May 24, 2011 | By: Catherine

AUTHORS: Juhi Muthal, Cindy Liu, Sabrina Sidhu, Catherine Gong



In school, students use different writing implements (ie #2 pencil, ballpoint pen, laptop) for assignments. Some of these are less effective than others and tire the students more quickly when a long assignment must be completed. We wondered how we could test which method is the most effective to use.


Then an experiment was developed. We used the Logger Pro program and the Vernier Handy Dynamometer sensor to test which activities were the most tiring to hand muscles. Muscles need oxygen in order to produce ATP, the energy source. However, if muscles are worked too hard or for too long, they cannot get oxygen quickly enough. With oxygen, the cells go through aerobic respiration. Without oxygen, cells go through anaerobic respiration or fermentation, which are less efficient and produce soreness (from lactic acid). In addition, muscles become sore after hard workouts due to DOMS (Delayed Onset Muscle Soreness). During extreme workouts, the muscles began to tear in microscopic areas. Afterwards, while the muscles rest, they rebuild and are sore due to DOMS during this time.


The goal was to see which method of writing would be the least tiring when taking notes or writing an essay, for instance. Each test subject engaged in one of the following activities for 2 minutes with their dominant hand: nothing (for reference), writing with a ballpoint pen, writing with a #2 pencil, typing, and hand exercises (stretching out your hand repeatedly, just as a slight addition to the main question). Then, the Dynamometer was used to test the amount of force their dominant hand could exert by squeezing with the hardest force and holding for 2-3 seconds, then slowly releasing. The amount of force the test subject would be able to exert on the sensor is inversely proportional to the amount of energy the activity will consume, so the activities with high force would be the least tiring while the activities with low force would be the most tiring. Initially, we guessed that the order of force would be (from highest to lowest or least tiring to most tiring):
* nothing (for reference)
1. hand exercises
2. typing
3. writing with a ballpoint pen
4. writing with a #2 pencil.

We had three test subjects, and each of their data graphs are presented below.
*Note: units - x-axis: time in seconds
y-axis: force in newtons

Subject 1: Sabrina
For this test subject, the order of effectiveness was:
*nothing (for reference)
1. typing
2. hand exercises
3. #2 pencil
4. ballpoint pen

Subject 2: Cindy
For this test subject, the order of effectiveness was:
*nothing (for reference)
1. typing
2. ballpoint pen
3. #2 pencil
4. hand exercises

Subject 3: Catherine
For this test subject, the order of effectiveness was:
1. hand exercises
2. ballpoint pen
3. #2 pencil
4. typing
*nothing (for reference)

This test subject had surprising results, and we suspect that her data was not recorded correctly or that some error occurred while conducting her tests.

Overall (on average), the order of activities (least to most tiring) was:
* nothing (just for reference)
1. typing
2. writing with #2 pencil
3. writing with ballpoint pen
4. hand exercises

Our results were extremely different from our hypothesis and came as a surprise. Hand exercises were actually the most instead of the least tiring, as they actually involved a lot of hand movement. Also, writing with a ballpoint pen was about the same as writing with a #2 pencil. The most crucial piece of data, however, was the information gathered regarding typing: that it was the least tiring and therefore, the most effective.

What are the implications of our results? First and foremost, schools should encourage typing instead of writing, similar to what Harker is doing (like in Mr. Contini’s class). More and more, teachers are allowing students to type essays and homework, which, as proven, is more efficient and less tiring. Not only that, but typing is also environmentally friendly (less paper used)...yet another reason why it should be implemented more often.


Also, we originally thought that doing “hand exercises” or stretching your hand over and over would help relax the muscles and help our hands, as most people encourage others to stretch before exercising. From our experiment, we saw that even though stretching for a few seconds may help, stretching for too long can actually make your hands (and arms) extremely sore, just like what happens when you exercise too hard or for too long. The muscles run out of oxygen and start to produce lactic acid and soreness.

In conclusion, our experiment demonstrated that typing is the superior means of writing, in terms of its benefits to students: it does not create soreness in the hands as frequently and, by extrapolation, allows students to write faster and continue for longer periods of time. Also, it does not create further soreness after class.
Monday, May 9, 2011 | By: Catherine

CSB #7 - Does exposure to trees and plants have health benefits?

At this time of year, allergies and AC keep many people indoors.
But for those who spend time outside in nature might be experiencing some surprising health benefits.

In a series of studies, scientists have found that when people spend a couple of hours in nature (parks, forests, some place with lots of trees), they experience increased immune function.


First off, stress level is reduced. However, it's not just that.

Scientists also found that phytoncides (chemicals in the air that plants emit to protect them from insects and rotting) are also beneficial to humans.

One of these studies was published in January. It took place in Japan.
280 people of good health were the test subjects.

One one day, some people were told to walk through a forest/area with lots of trees for a few areas. Actually, "Shinrin-yoku" or "forest bathing" had became a popular therapeutic practice in Japan.

The other people were instructed to walk through a city area.


On the second day, they traded places.

Scientists found that, "being among plants produced lower concentrations of cortisol, lower pulse rate, and lower blood pressure, among other things."
Cortisol - a steroid hormone produced by the adrenal cortex. It is released in response to stress. However, a high level of cortisol leads to many negative effects such as decrease in bone density & muscle tissue, higher blood pressure and lower immunity.


Numerous other studies have shown that being in forest surroundings seems to increase levels of white blood cells.


In one of these studies, men took 2 hour walks in a forest over two days. They had about a 50% increase in levels of white blood cells.


In another study, women spent time in forests and scientists found an increase in white blood cells in them that lasted about a week.

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I found this article really interesting because I spend a lot of time outdoors and I always felt better after spending some time outside.
I just assumed that being outside was good for me but I never had any evidence.


Citations -

ARTICLE: O'Connor, Anahad. "The Claim: Exposure to Plants and Parks Can Boost Immunity."
New York Times. N.p., 25 Apr. 2011. Web. 7 May 2011.
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PICTURE: http://www.ca.uky.edu/forestry/maehrbearky.php