Solution

We focus on a natural hormone in the human body, melatonin, as a strategy to improve sleep quality. The combination of exercise, nutrition, and sleep together provides factors that affect sleep which we will incorporate to help positively reduce fatigue for astronauts in space. Melatonin is one of the important hormones related to circadian rhythm; levels of melatonin will increase before sleep time. (Zhang et al., 2020) It is also regulated by exercise, a study has suggested that afternoon exercise may reduce melatonin secretion while morning exercise affects less than afternoon one in melatonin levels regulation (Carlson, Pobocik, Lawrence, Brazeau, & Koch, 2019). Moreover, several kinds of food contain high level melatonin (Meng et al., 2017); these different food categories benefit sleep also. (Doherty, Madigan, Warrington, & Ellis, 2019) Previous studies have tried to solve astronauts’ fatigue problem; however, often a light treatment or medication is used. (Wotring, 2015; Wu et al., 2018) Our project tries to use an easy and alternative method to achieve the same goal, alleviating astronauts’ fatigue and increasing astronauts’ quality of life.

In providing a customization of the time schedule, we consider two factors:

1) Docking time: Morning, Afternoon, and Evening

2) Task vs. No Task: If there’s a task, factors include exercise in morning, afternoon. If No Task, we divide by timezone.

3) Landing time: Morning, Afternoon, and Evening

Our customization of time schedule have a few restraints:

1. nap time has to occur either in morning or afternoon
2. exercise occurs either in the morning or afternoon
3. sleep time is fixed
4. meal time is fixed

Depending on the docking time and work time, the time of exercise, meal, nap and sleep times will change.

In total, there is a combination of 13 possible timelines:

Docking Time

Landing Time

Task vs. No Task 

The daily input of food intake would be used to calculate whether their food matches the 12 foods and beverages that contain known melatonin levels. Users will get weekly feedback of how many of the food items consumed during the week matches the 12 of the food and beverage with known melatonin levels. 

The 12 food and beverages are: yoghurt, apple, beef, lamb, pork, rice, corn, carrot, cauliflower, mushroom, cranberry, tomato

Method (Data Sets)

Our App, Astronaut Daily, incorporates research that shows three factors and activities (e.g., nutrition, level of exercise, and circadian rhythm) that influences melatonin levels. This background research is then used to suggest an optimal sleep schedule for users. Below is a chart of how food intake, circadian rhythm and the level of exercise can affect melatonin which in turn, affects sleep quality.  

Pre-Processing of Data

We use the following resources from NASA:

1. A list of food and beverages that astronauts are able to access on the International Space Station (Appendix B)
2. A list of food and beverages that contains levels of melatonin 
3. Dataset for the amount of duration of spacewalk from the NASA’s Data Portal: Extra-vehicular Activity(EVA)-US and Russia. 

First, we did a pre-processing for the two lists of food and beverages we found: List 1 is from a list of food and beverages that astronauts are able to choose on the International Space Station and List 2 is a list of food and beverages with the level of melatonin.  

In Python, we performed a match that finds the levels of melatonin from List 2 of the food and beverages and include it into another column in List 1.  

The final list of food and beverages (the food and beverages that astronauts are given with a column of melatonin levels) are then matched to each other and this list is saved into a MySQL database.

App Workflow

Our Android App, Astronaut Daily, is written in Java and using, an API, connected to Node.js which requests data from MySql Database.  

Results 

Below is a UI workflow of our App in Figma:

Our android app follows the 'Android App-Final Wireframe' in Figma. Our UI concept is in 'Android App-Final'. For both, you can press "play" to start the simulation of the prototype.

UI sharing link: https://www.figma.com/file/AL0fyg7kxtrmEoU7RTFmUO/Sleep-Shifting-based-on-Melatonin?node-id=80%3A2

To see the source code of the app, please visit:

Github: https://github.com/solarwomen/SpaceAppChallenge2020

NASA Resources and Datasets

Space Food and Nutrition:

https://www.nasa.gov/pdf/143163main_Space.Food.and.Nutrition.pdf

Dietary Sources and Bioactivities of Melatonin:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409706/

Limitation

1. We don’t have the melatonin levels of all food and beverage listed for the International Space Station.
2. We didn’t use machine learning to fully customize astronauts’ schedules. 

Impact

Sleep is quite important for astronauts because insufficient sleep is easy for astronauts to feel fatigue. Melatonin is a common hormone that is not only secreted by human beings but also in natural foods. With the regulation of melatonin, people sleep easier. Moreover, some foods, such as nuts, cherries, contain high levels of melatonin (Meng et al., 2017). Interestingly, exercise also affects melatonin. Morning exercise interferes with an individual’s sleep less than afternoon exercise does. With the integration of these factors and their functions, we hope to help people regulate their life and improve their quality of life.

Future

In order to break limitations in our current prototype, we suggest to calculate the exact amount of melatonin that astronauts intake, to detect what types of exercise that astronauts actually do during their exercise time, and to detect the melatonin shifting rate in order to make sure that the customized timeline is practical in the future.

Conclusion

Our project reschedules the timeline of astronauts’ daily schedule by providing an optimal exercise, nutrition, and sleep time. Thus, we suggest that our app “Astronaut Daily” may serve its use for astronauts in the space station.

https://drive.google.com/file/d/1OK1e2ESbnngf4M4xOz7405SQJ1sY6RH7/view?usp=sharing

Brainard, G. C., Barger, L. K., Soler, R. R., & Hanifin, J. P. (2016). The development of lighting countermeasures for sleep disruption and circadian misalignment during spaceflight. Curr Opin Pulm Med, 22(6), 535-544. doi:10.1097/MCP.0000000000000329

Carlson, L. A., Pobocik, K. M., Lawrence, M. A., Brazeau, D. A., & Koch, A. J. (2019). Influence of Exercise Time of Day on Salivary Melatonin Responses. Int J Sports Physiol Perform., 351-353. doi:10.1123/ijspp.2018-0073

Doherty, R., Madigan, S., Warrington, G., & Ellis, J. (2019). Sleep and Nutrition Interactions: Implications for Athletes. Nutrients, 11(4). doi:10.3390/nu11040822

Laurens, C., Simon, C., Vernikos, J., Gauquelin-Koch, G., Blanc, S., & Bergouignan, A. (2019). Revisiting the Role of Exercise Countermeasure on the Regulation of Energy Balance During Space Flight. Front Physiol, 10, 321. doi:10.3389/fphys.2019.00321

Meng, X., Li, Y., Li, S., Zhou, Y., Gan, R. Y., Xu, D. P., & Li, H. B. (2017). Dietary Sources and Bioactivities of Melatonin. Nutrients, 9(4). doi:10.3390/nu9040367

Wotring, V. E. (2015). Medication use by U.S. crewmembers on the International Space Station. FASEB J, 29(11), 4417-4423. doi:10.1096/fj.14-264838

Wu, B., Wang, Y., Wu, X., Liu, D., Xu, D., & Wang, F. (2018). On-orbit sleep problems of astronauts and countermeasures. Mil Med Res, 5(1), 17. doi:10.1186/s40779-018-0165-6

Zhang, F., Li, W., Li, H., Gao, S., Sweeney, J. A., Jia, Z., & Gong, Q. (2020). The effect of jet lag on the human brain: A neuroimaging study. Hum Brain Mapp, 41(9), 2281-2291. doi:10.1002/hbm.24945

1. https://www.nasa.gov/centers/johnson/pdf/584739main_Wings-ch5d-pgs370-407.pdf

NASA Resources and Datasets

Space Food and Nutrition:

https://www.nasa.gov/pdf/143163main_Space.Food.and.Nutrition.pdf

Dietary Sources and Bioactivities of Melatonin:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409706/