FitBits
January 15, 2008
Exercise ETC's Review of Exercise Related Research
Compiled by Chris Marino, MS, CSCS
Director of Education, Exercise ETC
Validating the Benefits Of a Personal Trainer for Women
Does having worked with a Personal Trainer increase the likelihood those women will select an adequate resistance when training alone? Researchers at the College of New Jersey say... YES!
Forty-six women with prior resistance training experience participated in the study, which was published in the Journal of Strength & Conditioning Research. Nineteen had worked with a Personal Trainer for at least 3 months prior to the study, and 27 had been resistance training for an equivalent time period independently. Using the chest press, leg press, seated row and leg extension machines, participants were asked to choose a resistance that could be performed for 10 repetitions.
Results showed that the PT group self-selected resistances that were on average ~51.4% of 1RM, nearly 10% higher than the non-PT group who chose weights that were ~42.3% of 1RM. In addition to the main findings, max strength for leg press and leg extension exercise was greater for the PT group, but not chest press. Interestingly, the women who worked with a PT reported consistently using 3 sets of 15-20 repetitions, while the non-PT groups reported doing 3 sets of 10-15 repetitions.
Strength researchers suggest that although beginners may benefit from using a resistance equivalent to 45% of their 1RM, as training age increases so must intensity to sustain progress. Consequently, more advanced trainees require 60-80% of 1RM to improve strength and hypertrophy, up to >85% in the most highly trained individuals.
Surprisingly, the women in the current study who were self-trained self-selected intensities that were more than 10% lower than the untrained women in a similar study published nearly one year ago. Unfortunately, although the women who had worked with a Personal Trainer used a greater resistance in this study, their self-selected resistance was still lower than is necessary for stimulating adaptation.
Ratamess, N.A., et al (2008) Self-selected Resistance Training Intensity in Healthy Women: The Influence of a Personal Trainer. Journal of Strength & Conditioning Research 22(1): 103-111.
[COMMENT: Some studies have shown that 80% of the people doing weight training in a gym -- male and female -- are not working at an intensity sufficient to produce results. This study would seem to confirm that.]
Are Fish Oil Caps Really Effective?
The purported benefits of Omega 3 Fatty Acids, specifically eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, are extraordinarily diverse. Studies have found that Omega 3's may accelerate fat loss, improve immune system function, reduce risk of CVD, decrease inflammation, lower triglyceride levels and blood pressure, and improve mental health, and more.
The two most common methods for increasing Omega 3 intake include consuming fatty fish and supplementing with fish oil capsules. As with most "supplements" questions exist regarding the bioavailability of the nutrients. A recent study published in the American Journal of Clinical Nutrition reported that both methods are equally effective.
Twenty-three women participated in the study. Eleven ate two servings of albacore tuna or salmon per week, while the other 12 women ingested an equal quantity of omega-3's. Researchers estimate approximately 485 mg/day in capsules.
Both groups of women experienced a significant rise in omega-3 fatty acids appearing in red blood cells and plasma, 40% and 60%, respectively after 16 weeks. RBC concentrations were greater in fish group at 4 weeks, but leveled off.
Although this research appears to favor the more convenient method of supplementation, it remains difficult to promote the use of fish oil capsules. First, the lack of regulation in the supplement industry makes it impossible to know the quality of the Omega 3's, which may vary considerably based on the manufacturer. Second, the quantity of Omega 3's necessary to experience benefits ranges from 1 to 4 or more grams of EPA/DHA per day (The American Heart Association now recommends between 1 and 4 g EPA/DHE per day depending on goals (i.e. prevention vs. treatment). To acquire that amount it would require up to 10 or 20 capsules depending on the product. Thus, eating fish a few times per week may remain the best option. Whole fish provides a lean protein source with additional health-promoting minerals in addition to Omega 3 Fatty Acids.
As always, anyone interested in using fish oil capsules should check with their physician first.
Harris, W.S., et al (2007) Comparison of the effects of fish and fish-oil capsules on the n–3 fatty acid content of blood cells and plasma phospholipids. American Journal of Clinical Nutrition.
[COMMENT: I've been telling people for years that we need more than 1 or 2 capsules of fish oil a day to see benefits, and this article supports that, suggesting between 10 and 20 capsules a day.]
Put on Your Boots!
Line Dancing Helps Osteoporosis
Physical activity is an essential component to the treatment of osteoporosis. Individuals with osteoporosis risk poor quality of life, disease or worse if they fail to or are unable to exercise regularly. Most women who are diagnosed with osteoporosis have been sedentary most of their life and may find traditional exercise unappealing. Scientists are getting creative.
A recent study published in Osteoporosis International reported that foot stamping, squats, and in-line dancing may be sufficient to preserve bone mass and prevent falls in previously sedentary, post-menopausal women. Researchers studied 45 post-menopausal women who were not taking bone-related medication. The women were divided them into 3 groups each of whom participated in a weekly line dancing class. One group also performed progressively loaded squats five days a week. And, in addition to line-dancing and squats a third group performed 4 foot stamps, two times per day, five days per week.
At the end of the study there were no significant differences in BMD, except for a trend related to stamp compliance. All participants, however, improved their squat performance (total number of reps), single-leg balance time, and sit-to-stand timed-performance.
The authors cite the greatest outcome of this study is the promise of exercise compliance amongst sedentary post-menopausal women. Line dancing is an appealing activity, whereas squats and foot stamping activities may be perceived as less of an inconvenience because they can be done anywhere.
Young, C.M., et al (2007) Simple, novel physical activity maintains proximal femur bone mineral density, and improves muscle strength and balance in sedentary, postmenopausal Caucasian women. Osteoporos Int. 18(10):1379-87.
Belief Systems About Eating Are Changing!
Although the word "diet" when translated means "a way of life," Americans have come to adopt its meaning as a short-term installment of a means to an end. In the 1990's, it was reported that ~35% of women and 23% of men were on a "diet" at any particular time. Interestingly, current statistics as reported by Reuters Health indicate a substantial decline compared to values a decade ago.
Port Washington, a New York-based NPD Group, Inc (a consumer marketing research firm that tracks American's consumption habits) that recently surveyed 26,000 Americans, reported that 29% of women and 19% of men are currently on a "diet," a reduction of 6% and 4%, respectively.
The firm speculates that a trend towards self-acceptance may explain the decline in dieting practices. According to their report, the percentage of adults who viewed an overweight person as unattractive has dropped by 50%.
Of the individuals who were on a "diet," improving health was the #1 motivation for 68% of respondents. In addition, one-third of dieters were not using a pre-designed "diet" but rather formulated their own approach, mostly based on portion control. Only 9% currently claim to be using an "extreme diet."
Although "dieting" is on the decline, the majority of Americans continue to perceive the need to lose approximately 20 lbs, as reported by 60% of respondents.
Stern, Andrew (2007) Americans opt for healthy eating, not diets. Reuters Health. Friday, January 4, 2008
[COMMENT: If Americans are actually eating healthier, this is good news. Diets don't work simply because people either give up on them (deprivation sucks) or go back to old habits when they reach their goals. The solution is a healthy lifestyle and good, whole foods (not processed) and regular exercise.]
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