And when I say "the scientist," I truly mean THE scientist. Honestly, it took months to nail down an interview with this extremely accomplished and busy woman; I am so pleased to say I finally got to "play reporter" with the head scientist of the NASA studies program: Dr. Ronita L. Cromwell.
Her credentials include both Bachelors and Masters degrees from University of Illinois at Chicago, as well as a Ph.D. from the University of Illinois at Urbana-Champaign – both with majors in Kinesiology and focus on motor control.
FAP Manager Joe Neigut, me, and Dr. Ronita Cromwell, Ph.D.
1. What's in the study plan for the rest of 2010 and 2011?
Dr. Cromwell: We're starting our vertical treadmill study. This study uses the eZLS to replace the daily loading stimulus to bones in an effort to mitigate bone loss that occurs during bed rest. We are also planning for our Functional Task Test (FTT), Integrated Resistance and Aerobic Training Study (iRATS) and testosterone supplementation study. The FTT will examine the physiological responses to a battery of functional tasks that mimic critical mission tasks. iRATS will evaluate a new training program to protect against loss of muscle, bone and cardiovascular function. The testosterone supplementation study will examine the ability of testosterone in combination with the iRATS exercise program to preserve and enhance muscle function.
2. What are some of the most common misconceptions you see in the press that you'd like to clear up? For instance, I for one am shocked that even after 3 interviews, a local news channel still called it a "Sleep Study" on the air!
That is one of the most common misconceptions. Because our subjects spend so much time in bed, the natural assumption is that they are sleeping. However, our subjects are awake between 6:00 am and 10:00 pm each day. They are only allowed 8 hours of sleep at night.
Another misconception is that our subjects get bored and do nothing while they are in the NASA facility. I think you can attest to the significant amount of scientific testing that goes on during our bed rest studies. We also ask that subjects have a goal to achieve when they come into our study. We have had some subjects who continue working if their job can be done on-line. Others have taken on-line courses, learned a new skill, studied a language, etc.
3. I was definitely never bored. In fact, I found the bottom of my email inbox for the first time since about 1994, it was awesome! As the senior research scientist, what is the biggest challenge in running these studies?
The biggest challenge to running these studies is the coordination of all the activities associated with these studies. A significant amount of planning goes into what is eventually carried out on the bed rest unit. Initially, the scientific content of studies must be compatible if we are going to run them as an integrated complement.
For example, the FTT, iRATS and testosterone supplementation studies fit very well together. Subjects who participate in the FTT study will serve as control subjects for iRATS and testosterone supplementation studies. Also, by integrating these studies, FTT testing will help to evaluate the iRATS training protocol. Once studies are integrated, there is a huge amount of preparation prior to admitting our first subject.
There are a number of approval processes that studies are subjected to at NASA that check for safety and readiness prior to implementation. Sometimes equipment must be purchased or built. And of course, subjects must be identified that qualify for the study. To support these activities the Flight Analogs Project (FAP) has a team skilled in all aspects of study planning and implementation.
4. You've been the project head for 3 years now; what has been the most satisfying thing about running these studies?
The support we provide to human research in the space program. Bed rest is an excellent analog for simulating the physiological changes associated with spaceflight in the bone, muscle and cardiovascular systems. By first doing studies in bed rest, we can determine whether or not a countermeasure may be useful for spaceflight. These ground studies can be accomplished more quickly and under greater scientific control.
5. What can you say about overall results? Are studies making a difference in our understanding of how to keep bodies healthy in long-term weightlessness?
One of the unique features of the NASA bed rest studies is the set of standard measures used for all of our studies. These measures comprise a multi-disciplinary assessment of each subject's physiological response. This allows us to examine all physiological systems for each study that is completed. For example, an investigator may be interested in an exercise countermeasure for preserving bone during bed rest.
This exercise countermeasure may also affect the muscle system, neurological system and cardiovascular system. The standard measures allow us to monitor these other systems and determine how they are affected by the countermeasure. Using the standard measures we have characterized the physiologic response to 6-degree head down tilt bed rest.
Results indicate significant loss of bone; 1-1.5% per month for bed rest depending on the area of the skeleton measured. Fluid shifts that produce cardiovascular changes demonstrate losses on average of 18% over the course of a bed rest study. This fluid loss affects subjects' orthostatic tolerance and reduces the ability of subjects to stand up without feeling light headed after bed rest. Muscle weakness is significant after bed rest and can affect posture and balance measures as well. These changes seen in bed rest are consistent with those observed in spaceflight. These results were published in a special supplement of the scientific journal Aviation, Space and Environmental Medicine in 2009.
6. How many men and women have now completed micro-gravity studies?
A total of 61 subjects have now completed our head down tilt bed rest studies. Of these, 40 were male and 21 were female.
7. When I went through the program, the goal was 90 days in bed. I hear it went down to 60 days, then 30. What were the reasons for this?
The bed rest studies were originally designed as 60-day studies. However, one of the early investigator studies that examined bone changes required that subjects spend 90-days in bed. So, other studies being run at that same time were shifted to 90-days as these subjects could be used as control subjects for the bone study. We continued to take measures at bed rest day 60, however. Once the bone study was completed, we assessed the 60-day measures and felt comfortable returning to a 60-day bed rest platform.
The 30-day studies were designed based on requirements of the participating investigators. Studies integrated into the 30-day platform were primarily to develop or validate methodology and/or equipment. Therefore, a 30-day platform was adequate to obtain the needed data.
8. Is there anything else I haven't asked that you would like to clarify?
Definitely let your readers know that we are always recruiting. They can call 1-866-JSC-TESTor go to https://bedreststudy.jsc.nasa.gov.
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