The Affect of a Ventilated Helmet on Physiological Load

Not Applicable

• Conditions: Physiological Strain
• Interventions: Procedure: Ventilated Helmet

• Registration Number: NCT01595906
• Lead Sponsor: Medical Corps, Israel Defense Force

Brief Summary

The use of infantry helmets under heavy heat stress conditions, during physical exertion, may hinder the body's ability to effectively dissipate heat from the head area, thereby damaging the soldier's function. Therefore head cooling may potentially enable a longer duration of activity until reaching fatigue. An improvement in function may also be possible.The purpose of this research is to determine the extent of the cognitive and physiological strain caused by wearing a helmet under exertional conditions while exposed to heavy heat stress and to evaluate the effect of a unique ventilation system connected to the helmet on strain reduction.

Detailed Description

12 young, healthy civilian volunteers, aged 21-28 will participate in the study. Following a day of examinations and 6 days of acclimatization in a climatic chamber in accordance with a well accepted protocol, the subjects will undergo 3 days of experiment that will include exposure to hot environmental conditions with different helmet-wearing scenarios, while wearing uniform and a combat vest: (a) without a helmet (b) with a helmet (c) with a helmet connected to a ventilation system. All 3 scenarios will include a two hour effort (walking on a treadmill) in heavy heat stress in the climatic chamber at our institute (the Heller institute of medical research).

Study Timeline

• Study First Submitted: 2012-03-22
• Status Verified: 2012-05
• Study First Submitted QC: 2012-05-09
• Study First Posted: 2012-05-10
• Last Update Submitted: 2012-05-14
• Last Update Posted: 2012-05-15
• Study Start: 2012-09
• Primary Completion: 2012-10
• Study Completion: 2013-02

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Male
• Target Recruitment: 12

Inclusion Criteria

• healthy civilian volunteers
• aged 21-28
• without known medical illnesses or medication use

Exclusion Criteria

• the existence of or suspicion of existing cardiac or respiratory disease
• hypertension
• diabetes
• any hormonal disease or any other chronic illness that may inhibit participation in the experiment
• infectious disease 3 days prior to the experiment.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
The experiment subjects	Ventilated Helmet	The subjects will undergo: 1. 6 acclimatization days carried out by a standard protocol including a daily 2 hour effort performed in a climatic chamber, during which the subjects walk on a treadmill at 5km/h on a 2% incline under heat conditions (40 deg. centigrade \& 40% RH). Core (rectal) and skin temperatures and heart rate will be monitored continuously. 2. Three consecutive days including 3 scenarios: 1. Without a helmet b.With a helmet c.With a ventilated helmet During the experiment days the subjects will be exposed to the following protocol : A 5 minute sitting, performing cognitive tests on a computer for 15 min, 120 min walking on a treadmill at 5km/h on a 2% incline, at the end of the effort the same cognitive tests will be repeated for extra 15 min, 155 min in total.

Primary Outcome Measures

Name	Time	Method
Physiological strain	9 days	The physiological strain will be determined by body core temperature and heart rate of the subjects during a heat tolerance test(HTT).

Secondary Outcome Measures

Name	Time	Method
Rectal temperature	9 days	The Rectal temperature will be mesured by a rectal thermistore during each HTT
Skin temperature	9 days	The Skin temperature will be mesured by skin thermistores on 4 sites (chest, leg and arm and head).
Heart Rate	9 days	Heart rate will be monitored using a polar watch.
Sweat Rate	9 days	Sweat rate will be calculated from the patient's weight and his water balance

Trial Locations

Locations (1)

Heller insitute, Sheba hospital; 🇮🇱 Ramat-Gan, Israel