Condition category
Musculoskeletal Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
Hyperbaric oxygen therapy (HBOT) involves a person breathing pure oxygen at higher pressure than normal air pressure. Air normally contains about 21% oxygen and 78% nitrogen, so HBOT provides more oxygen to the body than is normally breathed in. It is thought that HBOT might results in muscle injuries healing more quickly, which would be an advantage to those playing sport competitively or professionally. This study aims to investigate whether HBOT improved recovery of muscle soreness and strains caused by exercise in baseball players.

Who can participate?
Professional or amateur male baseball players in training or the baseball season who have a muscle injury caused by exercise.

What does the study involve?
The participants will be randomly allocated to one of two groups. Both groups will spend 10 sessions of 100 minutes over 5 weeks in a pressurised chamber, where the pressure will be raised to above normal. One group will breathe pure oxygen while in the chamber and the other will breathe normal air. Oxygen and nitrogen are colourless gases with no smell so the participants will not be able to tell which gas they are breathing. Before the first session, after the fifth session, after the last session and 2 weeks after the last session, the participants will be asked give a blood sample and to rate their muscle pain and how much it affects their daily activities.

What are the possible benefits and risks of participating?
Those who breathe pure oxygen might experience earlier recovery of the muscle injury. There is also a small risk of side effects caused by absorbing too much oxygen.

Where is the study run from?
Kaohsiung Chang Gung Memorial Hospital, Taiwan, Republic of China

When is the study starting and how long is it expected to run for?
August 2013 to August 2016

Who is funding the study?
Chang Gung Research Fund (Taiwan)

Who is the main contact?
Miss Chen-Yu Chen

Trial website

Contact information



Primary contact

Dr Wen-Yi Chou


Contact details

123 Ta Pei Road
Niao Sung

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number

Chang Gung Research Fund grant CMRPG8D0411

Study information

Scientific title

Hyperbaric oxygen therapy influence of high-intensity athletes in vivo metabolic indicators


Study hypothesis

HBOT could facilitate the early recovery of exercise-related muscular injury and could therefore be beneficial for elite athletes.

Ethics approval

Approved 21/08/2013, Institutional Review Board (IRB) of Chang Gung Medical Foundation (123 Dinghu Rd, Guishan Township, Taoyuan County, Taiwan (R.O.C.); +886 3 3196200 ext 3707/3703;, ref: 102-2994B

Study design

Prospective randomized double-blind controlled study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use contact details to request a participant information sheet.


Exercise-related muscular injury


41 participants were recruited between June 2014 and December 2015 and were divided into study group and control group with 20 and 21 participants. All the participants received either HBOT or placebo sessions twice in a week. The study group and the control group stayed in a hyperbaric chamber pressurized to 2.5 and 1.3 atm, and breathed pure oxygen and general air, respectively. The duration of each session was 100 mins, and 10 sessions were completed in 5 weeks for each participant.

Intervention type



Drug names

Primary outcome measure

1. Serum creatine phosphokinase (CPK)
2. Serum glutamic-oxaloacetic transaminase (GOT)
3. Serum myoglobin
4. Blood urine nitrogen (BUN)
5. Serum lactate
Data were collected before the treatment (T1), end of 5th HBOT (T2), end of 10th HBOT (T3), and 2 weeks after the 10th HBOT (T4).

Secondary outcome measures

1. Pain intensity assessed using the Brief Pain Inventory before the treatment (T1), end of 5th HBOT (T2), end of 10th HBOT (T3), and 2 weeks after the 10th HBOT (T4)
2. Pain interference assessed using the Brief Pain Inventory before the treatment (T1), end of 5th HBOT (T2), end of 10th HBOT (T3), and 2 weeks after the 10th HBOT (T4)

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Aged 20 years or older
2. Diagnosed with prolonged (more than 2 weeks) exercise-induced muscular soreness or pain with grade I muscle strain of the extremities
3. Currently under intensive and regular baseball training or regular baseball season

Participant type


Age group




Target number of participants

46 (5 cases loss)

Total final enrolment


Participant exclusion criteria

1. Pneumothorax
2. Upper respiratory tract infection
3. Recently received chest or ear surgery
4. Claustrophobic

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Kaohsiung Chang Gung Memorial Hospital
123, Ta Pei Road, Niao Sung District

Sponsor information


Chang Gung Memorial Hospital

Sponsor details

123 Ta Pei Road
Niao Sung District
+886-7-7317123 ext 2450

Sponsor type

Hospital/treatment centre



Funder type

Hospital/treatment centre

Funder name

Chang Gung Medical Foundation

Alternative name(s)

Funding Body Type

private sector organisation

Funding Body Subtype

Trusts, charities, foundations (both public and private)



Results and Publications

Publication and dissemination plan

Planned publication in a high-impact peer-reviewed journal.

IPD sharing statement:
The datasets generated and/or analyzed during the current study during this study will be included in the subsequent results publication.

Intention to publish date


Participant level data


Basic results (scientific)

Publication list

2019 results in (added 11/02/2020)

Publication citations

Additional files

Editorial Notes

11/02/2020: Publication reference added. 29/03/2019: Internal review. 21/03/2019: Trial's existence confirmed by Chang Gung Medical Foundation.