Ignite Creation Date:
2024-05-06 @ 6:46 PM
Last Modification Date:
2024-10-26 @ 2:54 PM
Study NCT ID:
NCT05773469
Status:
COMPLETED
Last Update Posted:
2024-01-11
First Post:
2023-03-06
Brief Title:
Energy Balance in Extreme Environments Finding the EI Limit
Sponsor:
University of Exeter
Organization:
University of Exeter
Study Overview
Official Title:
Energy Balance in Extreme Environments Metabolic Adaptation to Energy Expenditure and Finding the EI Limit
Status:
COMPLETED
Status Verified Date:
2024-01
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
StOMPE
Brief Summary:
This project is feasibility study looking at extreme exercise and possible diet intervention study to counter muscle and weight loss during a 2 person Greenland Ski Traverse in April 2023 By increasing energy intake to above the currently theoretical capacity 25 x RMR the aim is to test a method to find out if there is a maximum to energy intake and whether energy deficit can be minimised weight loss attenuated and whether muscle can be preserved If not what are the likely adaptive mechanisms and use this to inform future work on dietary interventions
Detailed Description:
Prolonged endurance events provide a unique opportunity to study the physiological limits of human performance When nutrition is adequate maintaining weight is directly related to energy expenditure In extreme environments however such as ocean rowing the investigators have shown that rowers lost 10 weight had a high energy expenditure 5000kcald or 31 x basal metabolic rate which was not met by energy intake EI Even in the presence of over 5000kcal food per day rowers chose to eat only 3800kcald 24 x RMR and lost weight rather than eat more It is also rare outside of elite performance that EI is above 25 x RMR and is suggestive of some sort of regulatory mechanism Previous work has shown that high energy expenditures EE are not sustainable over long periods and that EE decreases with duration plateauing at around 25 x RMR This is in attempt to balance energy requirements in order to minimise body mass loss and increase chances of survival Using data from the previous PhD study in ocean rowers Holsgrove-West 1st PhD study and extrapolating data from the studies used to model TEE and duration and overfeeding studies voluntary energy intake calculated from body mass loss were consistently around 24 x RMR suggesting a possible numerical value to the limit of EI This has not been measured experimentally If the theory of maximal EI is true any intake above the maximum 24 x RMR cannot be used for energy and would be excreted Any BM loss would therefore reflect difference between EE and the maximal EI not the actual EI To investigate the EI limit therefore requires simultaneous measurements of EE EI and body mass changes whilst ensuring EI above the theoretical maximumIn the presence of energy deficit and body mass loss ocean rowers demonstrated an adaptive response by selectively maintaining or losing muscle Loaded muscles were preserved whilst unloaded muscles atrophied An obvious countermeasure could be to load the muscles that wasted but to what expense With finite energy intake and greater demand from the muscle mass other components of EE such as RMR NEAT or exercise component may compensate or endure a greater body mass loss This interaction warrants further investigation Logistically it is difficult to ask rowers to exercise mid-race and compliance would be unknown An expedition that involves greater muscle involvement and high EE is needed Trekking across Greenland provides the high EE environment without the lower limb disuse In addition due to logistical reasons of sample storage in ocean rowing energy expenditure and intake were collected only in the final week of the row and energy balance did not match with body mass loss This would indicate a different energy deficit and different energy expenditure or intake earlier on in the row These initial acute changes are unknown and possibly responsible for the large weight loss seen by the end of the row This project will attempt to fill that gap and measure these initial changes by measuring daily EI and EEEI is rarely measured alongside EE and body mass loss and instead inferred from EE This study aims to establish whether this maximal EI exists by directly measuring both components of energy balance and how the body compensates with changes in the components of EE
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None