begin to dig: Pick it Up. Again. Research poses correlation of resistance training reps to motivation type.

Saturday, September 18, 2010

Pick it Up. Again. Research poses correlation of resistance training reps to motivation type.

Do you think someone who is extrinsically motivated (i want to win a gold medal) vs intrinsically motivated (i want to be the best i can be) is more or less likely to do more or less resistance work?

Yes, that's a question that's been asked in a recently published study on who uses fitness centers. The authors' abstract reads:

There is a need to better understand the behavior and sense of motivation of fitness center participants. The purpose of this study was to assess whether or not demographic characteristics and health self-determinism (intrinsic or extrinsic motivation) of fitness center participants were predictive of their levels of resistance training. A cross-sectional design was used; participants were recruited via the Internet to complete an online survey. There were 185 participants (age = 39.1 ± 11.3 years) in the study. The majority of respondents reported having carried out levels of resistance training that met national health organization recommendations. Regression analysis of the data revealed that health self-determinism predicted quantity of resistance training reported (p = 0.014), whereas demographics did not. Being intrinsically motivated to health self-determinism predicted meeting national resistance training recommendations compared to participants extrinsically motivated (p = 0.007). For those who work with fitness center participants, our findings are useful by identifying participants as a predominantly intrinsically motivated group of people that performs adequate quantities of resistance training; the methodology employed in this study can be used to identify participants in need of increased levels of resistance training and heightened sense of motivation to do so.

THe study was entirely based on self-reporting both of participation in lifting and attitudes. So using the Health Self-Determinism Index and calculating resistance activity based on input from Paffenbarger's Physical Activity Questionnaire with the following:

From responses to the 4 resistance training questions, we extracted the total resistance training carried out in units of total repetition-muscle groups per week. Total repetition-muscle groups per week was calculated as a product of the following: type (number of different muscle groups exercised per week); duration (number of repetitions of each different muscle group exercised per day); frequency (number of days per week for each muscle group exercised). We based our determination of whether or not participants met national recommendations for resistance training upon a calculation of total repetition-muscle groups per week. We considered participants to have met national recommendations for resistance training if they carried out a minimum total of 128 repetition-muscle groups per week (8 muscle groups per day × 8 repetitions per muscle group × 2 d·wk⁻¹).

Here's an amazing finding: people who self-reported about using the gym for 3 months (or at least had been members for that long) and met the guidance for sufficient exercise were the MAJORITY of the respondents: "The majority of subjects met national resistance training recommendations." Amazing. 185 self-selected participants who self-reported about their participation met the benchmark.

So what does that tell us? Well, not much. Except that self-reporting is notoriously inaccurate as a measure of actual actions, so it's rather a surprise that the authors say that the participants DO this amount of training rather than "report doing" this amount of training.

Does that mean the data's useless? Not necessarily. When the authors start doing gnarly stats on amount of self-reported work, some interesting differences emerge.

Key finding? According to the authors it's that demographic information tells us nothing about who's going to work out more. I'd only say it may tell us nothing about how self-reporting of workouts is expressed. Until there's a measure to validate the accuracy of the self-reports, who knows?

But what the claim means is that age, gender, years of working out - none of that is indicative of amount of (reported) resistance training.This idea of motivation type, however, does correlate. There are likewise some interesting correlations about who is likely to show up as "intrinsically motivated"

Those participants extrinsically motivated to health self-determinism tended to be younger (age = 34.1 ± 12.5 years) than those intrinsically motivated to health self-determinism (age = 39.7 ± 11.1 years) (t(183) = −1.974, p = 0.050). Intrinsically motivated participants tended to have a higher level of education than those extrinsically motivated (Mann-Whitney U, U = 907.000, p = 0.008) and reported having lower annual income than those intrinsically motivated (Mann-Whitney U, U = 930.000, p = 0.014). Having an education level of high-school diploma or less was only slightly, but significantly, predictive of the likelihood that a study participant would be extrinsically motivated toward health self-determinism (OR = 0.286, 95% confidence interval = 0.110-0.747, p = 0.011).

The authors however acknowledge, that despite being their biggie determinant - the difference in motivation type - the difference between ex and in motivators is pretty small. So what else is at play?

Because health self-determinism only accounted for a small proportion of the variance in resistance training in our study, other factors may contribute to why fitness center participants tend to be motivated or unmotivated to engage in resistance training. For example, Trost et al. (¹²) suggested that social influence, satisfaction with the facility, and time for exercise may all be relevant factors for predicting aerobic physical activity (³¹) and may also be relevant factors for resistance training.

Other limitations?

There are various other possible explanations as to why fitness center participants tend to carry out varying levels of resistance training that we did not measure in our study. For example, fitness center participants who work out with a personal trainer may tend to carry out higher levels of resistance training compared to their counterparts who do not work out with a personal trainer.

Right - so if someone has a trainer, maybe that's why they're showing up as working out more. Maybe. And we have no comparison with folks who work out at home, either.

So why limit the study to fitness center members? Putatively, the goals are to help fitnesses centers identify those less likely to move it move it by administering the same questionnaire as the study used. Also, it's a guide for writing ads: if you're gearing to a population that's correlated with extrinsic motivation cues, does a center's ads connect with those cues? Help up participants' motivation so they'll workout more.

Summary - interesting study; some nice ideas. It would be interesting to see how well the self-reporting correlates with actual fact. It may be that there's also under and not just over-reporting of activities as well, or that actual action vs self-reporting is so out of alignment that the proposed strategies are not sufficient to make a break through.

Citations

Kathrins BP, & Turbow DJ (2010). Motivation of fitness center participants toward resistance training. Journal of strength and conditioning research / National Strength & Conditioning Association, 24 (9), 2483-90 PMID: 20802286

&NA;, . (1997). Paffenbarger Physical Activity Questionnaire Medicine& Science in Sports & Exercise, 29 (Supplement), 83-88 DOI: 10.1097/00005768-199706001-00017

Cox CL (1985). The Health Self-Determinism Index. Nursing research, 34 (3), 177-83 PMID: 3846926