Posts Tagged ‘research’

To Stretch or Not?

Please let me apologize for our extended hiatus! I’ve been teaching like a crazy person all summer, Kevin has been working tons of overtime, and unfortunately the blog had to go on the backburner for a bit. But, now it’s almost fall and we should have plenty of time for our blog. Hooray! 🙂

One great thing that happened this summer was that a friend of mine guest lectured in one of my classes, and I learned a ton! He is a certified strength and conditioning coach, has a PhD in Exercise Physiology, and is an accomplished powerlifter. He knows a ton about weight lifting and I was thrilled to have him give a three hour lecture (plus, it meant I didn’t have to lecture that day).

The coolest thing I learned was how much convincing research there is about stretching; mostly, it’s stupid. Shocked? I was. Every team I’ve ever been on has started every practice by stretching. For those of you who work out, how many of you feel that you need to stretch before you start? It’s just good common sense, right? If you care at all about athletic performance, apparently not.

A study done at LSU looked at the effects of static stretching on sprint performance. The athletes stretched for 15 minutes (think bending down and reaching for your toes for 30 seconds at a time), and then did a 20 meter sprint as fast as possible. They compared the running time without stretching and interestingly, all the runners were significantly slower after stretching. The researchers even asked the runners which trial they thought was fastest, and every runner said they felt faster and more confidant on the stretching trial. But they were slower!

The same effect was found in endurance running as well. So why do we continue to stretch? For most of us, it’s habit. Our coaches told us to do it, our friends do it, and we’ve been doing it for years, but is it any good? What about injuries? For the longest time, I continued to stretch because I was afraid that if I didn’t, I’d  get injured. The research is mostly…inconclusive. (Here’s a link to a nice review article if you are nerdy like me) The problem is that stretching decreases the elasticity of a muscle, making it more compliant. Think about stretching a rubber band around a chair and leaving it for awhile. Not so stretchy. If you need to do a powerful, fast sport, you need all the elasticity you can get, and reducing elasticity can actually lead to injury. Even  low- intensity activity requires muscle elasticity, and while it probably doesn’t increase injury, it certainly doesn’t prevent it.

However, don’t take all this to mean you shouldn’t do any kind of warm-up before exercising. A slow jog and some dynamix stretching is wonderfully effective. Think leg swings, high knees, and butt-kicks to get you started.

Do you guys stretch before you exercise? What do you do and do you swear by it?

-Sara

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Hey guys! I was scouring the internet for interesting weight loss info and came across this article about sleep and weight loss. Hope you like it! -Sara

Weekly Review: Your Morning Starbucks

To say that I love coffee would be quite an understatement; I begin each morning with a large cup, and I’m craving my second by 2 pm. Sometimes, I’ll even have a third after dinner. I know, I have a problem. But, I don’t think I’m alone in my glorious addiction to coffee. Did you know that Americans drink 1.4 (women) to 1.9 (men) cups of coffee per capita per day? And, just so I don’t have to feel too bad about my caffeine habits, among coffee drinkers, Americans consume 3.1 cups  of coffee per day (National Coffee Association).

Being the scientist that I am, I have often wondered, “Is this healthy?” Growing up, you may have been told that coffee will stunt your growth, which is why I waited so long to start (I am only 5’2.5″). But now people are starting to say good things about coffee; it’s full of antioxidants, it reduced depression and it may prevent cancer. Or it causes cancer (depends on which research you’re reading 🙂 ) So, I thought I would search through some of the current literature and give you all an update on where the scientific and medical community stands on your morning cup of joe.

The Good News: There are definitely benefits to regular coffee consumption, but do take note that the amount of coffee you consume and what you consume it with (do you take your coffee black or with cream and artificial sweetener?) may affect the potential health benefits. Long-term coffee consumption has been associated with a decreased risk of Type II diabetes, and in some cases a reversal or decrease in symptoms. Coffee may also be protective against certain types of cancer including pancreatic, endometrial and colorectal. The caffeine in coffee increases your cognitive function and may increase long term memory. There is also some preliminary evidence that long term coffee consumption may help prevent some of the signs of aging in the brain, due to it’s high anti-oxidant properties.

The Bad News: Coffee consumption may not be so great for your blood pressure and your heart. In people who had already been diagnosed with hypertension, drinking coffee elevated blood pressure for 2-3 hours after consumption. This may not seem like such a big deal, but if you have 2-3 cups throughout the day, you may be spending a great deal of your time with an elevated blood pressure. This could put you at an increased risk for heart disease. There have been several large studies trying to determine whether coffee could directly increase your risk for a heart attack and so far the results have been mixed. Here’s a nice review if you’re interested.

Conclusion: Overall, moderation is the key. In most of the studies that found detrimental effects of coffee, the drinkers had more than 3 cups per day, but those who consumed 1-2 still retained some protective benefits. But, be cautious if you have or are at risk for hypertension, because you could be making your condition worse. For most of us however, it seems that 1-2 cups of deliciousness everyday may actually be beneficial! Hooray! So, drink up and enjoy.

-Sara

Why is sitting so bad?

After reading our last post, you may be wondering why it is that sitting for long periods of time can put you at risk for heart disease. Enter: Dr. Sara Mahoney, Exercise Physiologist! Ta daa! There are actually a couple of interesting reasons why sitting for long periods is bad for your health, and I think once you understand, you’ll be more motivated to move around.

1. Lipoprotein Lipase (LPL). This is an enzyme that helps you break down fats. Remember a few posts ago, I taught you how the body can either use fats or carbohydrates for energy? Well, fats give you a lot more bang for your buck, but most of them are stored away in your adipose tissue (fat stored under your skin). In order to use them for energy, you have to break them down from their triglyceride form into a free fatty acid, and in order to do that  you need LPL. What’s crazy about LPL it’s really only released during muscle contraction. So, if you spend your entire day sitting down, you really aren’t contracting very many of your muscles, and therefore your LPL levels plummet. Just going from a sitting to a standing position significantly increases the number of muscles you are contracting and increases the amount of fat you burn for energy.

2. VO2 (volume of oxygen). VO2 is a measure of how hard the body is working by measuring how much oxygen you take in with each breath and use throughout the body. You can also use VO2 to calculate the number of calories per minute you burn. When you are sitting down your VO2 is about 2-3 ml/kg/min, but when you  just stand up, your VO2 doubles! That means your body is working twice as hard when you are standing up versus when you stay seated.

3. Total calorie burn. Studies have shown that people who spend the day walking around  burn up to three times the number of calories as those who spend the day at a desk. Sitting is the most sedendary thing you can do. Even independent of evening workouts, this increased total calorie burn from an active day often leads to smaller waist circumferences and lower total body weight, reducing your risk for cardiovascular disease.

So, in summary, just by walking around during the day, you are helping your body burn more fat, burn more calories and reduce your waistline. All of these factors can reduce your risk for heart disease. For tips on how to get moving during the day if you have a desk job, check the previous post!

-Sara

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