Doorway pec stretch

Key points

In 50 people without shoulder disorders, the pectoralis minor, a smaller chest muscle beneath the pectoralis major, was 2.24 cm longer during a one-arm self-stretch¹. A later paper describes that stretch as done standing, with the palm against a door frame².
In 18 healthy men, an ultrasound index of pectoralis minor lengthening was highest in horizontal abduction (drawing the raised arm backward) with the arm raised to 90° or 150°³.
Studies disagree on whether weeks of stretching lengthen the muscle⁴. A meta-analysis (a study that pools the results of several earlier studies) of six trials in 263 adults concluded that static stretching alone does not⁵. In a trial of 60 young women with rounded shoulder posture, a length test improved from baseline over three weeks, with no group that did not stretch⁶.
In 38 healthy, active people, 7 weeks of pectoralis major stretching raised shoulder extension range by 6%⁷.
Trials of one stretching session before the bench press differ: some found no change in maximum strength, and others found a fall^8,9.

Movement

The position studies describe

One study compared three stretches of the pectoralis minor, and a later paper describes its one-arm self-stretch^1,2. The person stands with the shoulder in 90° of abduction, the arm lifted out to the side². The elbow is bent to 90° and the palm rests against a door frame or another flat, rigid surface². The trunk then turns away from that shoulder².

A trial in 60 young women with rounded shoulder posture used the same standing position, with the palm on a flat surface⁶.

The versions studies have used

Other studies used related chest stretches, done alone or by another person²:

Corner stretch. One six-week home programme placed the hands above the head on adjoining corner walls, and the person leaned in².
Straight arm on a wall. A 7-week trial used a straight arm against a wall, at shoulder height and at 45° to the ground⁷.
Passive stretch, lying face-up. In a study of swimmers, the arm was moved into horizontal abduction (drawing the raised arm backward) for them².

What it loads

The pectoralis minor

The pectoralis minor is one of the muscles that position the pectoral girdle, the shoulder blades and collarbones¹⁰. The three-stretch study measured its length with electromagnetic motion capture during each stretch¹. In 50 people without shoulder disorders, the pectoralis minor lengthened more during a one-arm self-stretch than during two stretches given by another person¹.

Pectoralis minor lengthening (cm). Bars start at zero; the table below gives each value with its source.

Stretch	Pectoralis minor lengthening
One-arm self-stretch	2.24 cm¹
Manual stretch by another person, lying face-up	1.69 cm¹
Manual stretch by another person, sitting	0.77 cm¹

How arm height changed the readings

One study tested nine stretch positions in 18 healthy men³. It used shear wave elastography, an ultrasound method that estimates how stiff a tissue is, as an index of how far the muscle was lengthened³.

Readings for the pectoralis minor were significantly higher in horizontal abduction with the arm raised to 90° or 150° than in the other positions³. Those two heights did not differ significantly³. Across the nine positions, the index was highest in horizontal abduction at 150°, then 90°, then 30°³. It was lower in scapular retraction (drawing the shoulder blades back toward the spine) and lowest in shoulder flexion, raising the arm forward³.

The pectoralis major

The pectoralis major is a large, fan-shaped muscle, typically with a clavicular, a sternocostal and an abdominal part¹¹.

In an elastography study of 15 men, the position that most lengthened it differed by part¹². For the clavicular part, it was horizontal abduction with the arm 45° or 90° out to the side¹². For the abdominal part, it was horizontal abduction at 135°, with pelvic rotation and external rotation (turning a limb outward)¹².

The shoulder joint and one nerve

The door-frame position holds the shoulder at 90° of abduction². A cutting study in cadavers (bodies donated for study) concluded that what limits external rotation changes with arm position¹³. As the arm nears 90° of abduction, it named the inferior glenohumeral ligament, a ligament of the shoulder joint¹³.

In 4 cadavers, a positioning test strained the ulnar nerve, which runs past the inner elbow, by 2.1% at most; shoulder abduction added most¹⁴.

How the body adapts

After one session

Two studies measured the pectoralis minor straight after passive stretching^2,15:

In 50 shoulders of 29 college swimmers without symptoms, two 30-second holds increased its length significantly, compared with control shoulders². Neither of the two stretches tested changed how the scapula (shoulder blade) moved straight afterwards².
In 15 healthy men, 5 minutes of passive horizontal abduction with the arm raised to 150° lowered its stiffness by 3.2 kPa¹⁵. When the arm was then raised sideways, the shoulder blade showed up to 4.8° more outward rotation and 3.3° more backward tilt¹⁵.

Whether the muscle gets longer over weeks

A review of pectoralis minor syndrome states that the stretching techniques described for lengthening the muscle have had mixed results⁴.

Three sources found no change^5,16,17. One pooled analysis of six randomised controlled trials in 263 adults concluded that static stretching alone has no effect on pectoralis minor length⁵. A randomised controlled trial is a study that assigns people to groups by chance, then compares the groups.

One trial took 25 people with shoulder pain and 25 healthy people with a tight pectoralis minor¹⁶. Six weeks of daily stretching changed its length in neither group¹⁶. In a trial of 80 adults with subacromial pain syndrome (a shoulder pain condition), one group added pectoralis minor stretching to a 12-week exercise programme¹⁷. Adding it made no difference to the muscle’s resting length¹⁷. A length index favoured the stretching group by 0.3%¹⁷.

Two trials found a change^6,18. In the trial of 60 young women, both groups stretched, and both improved from baseline on a pectoralis minor length test⁶. That trial had no group that did not stretch⁶.

In 39 college women swimmers without symptoms, a different technique was used twice a week for 6 weeks¹⁸. It was a 3-second pectoralis minor stretch followed by a 5-second isometric contraction, in which the muscle works but the joint does not move¹⁸. Resting length rose more than with no intervention¹⁸.

Posture and the shoulder blade

Sources also disagree on posture^19,20. A review looked at people with abducted shoulder blades, which sit away from the midline¹⁹. It reported intervention studies showing that chest stretching, alone or with strengthening, can alter the resting position of the scapula¹⁹. The same review noted a dearth of high-quality studies¹⁹. In 52 healthy students with rounded shoulder posture, two resting scapular rotation angles fell after five sessions in a self-stretching group, compared with controls²¹.

Other studies point the other way^20,22:

In 20 people with forward shoulder posture and no symptoms, 6 weeks of pectoral stretching plus strengthening did not change resting scapular posture²².
In 20 people with forward shoulder posture, the posture decreased significantly more in a group that strengthened than in a group that stretched²³.
A meta-analysis of 23 controlled trials in 969 healthy people found that stretching did not change posture of the spine, lower back and pelvis²⁰. Strengthening programmes were associated with large improvements²⁰.

Range and strength after weeks of chest stretching

In one trial, 38 healthy, physically active people were randomly assigned to pectoralis major stretching or a control group⁷. After 7 weeks, shoulder extension range of motion (how far a joint moves during a movement) rose by 6% in the stretching group⁷. Maximal isometric torque (a turning force) rose by 11% at a long muscle length, but not at a short one⁷. The stiffness of the pectoralis major did not change⁷. The authors suggest that greater stretch tolerance, or changes in other structures, might explain the gain in range⁷.

One eight-week study measured the bench press²⁴. In 31 recreationally active people, 18 stretched the pectoralis major for 15 minutes a day²⁴. Their one-repetition maximum, the heaviest load a person can lift once, rose 7.4%²⁴. The effect on isometric strength was not significant²⁴.

One session before bench pressing

Trials of stretching just before bench pressing differ in their results^8,9:

Who was studied	Stretching before the test	What was found
19 college-aged men and 32 women	Static routine with the chest, three 15-second repetitions	One-repetition maximum no different from no stretching⁸
20 men, 9 untrained and 11 trained	A passive static stretching programme	One-repetition maximum significantly lower in both groups⁹
Men in two experiments, 19 and 15	One, two or three 20-second stretches, or one 40-second hold	Repetitions to fatigue unaffected by the 20-second stretches; fell after the 40-second hold²⁵

Trials in people with shoulder pain

In the trial of 80 adults with subacromial pain syndrome, adding the stretch made no difference to a shoulder function score or to pain¹⁷. On a second disability questionnaire, the group that did not add the stretch improved more, by 5.4 points¹⁷. In the 25 people with shoulder pain who stretched daily for 6 weeks, arm, shoulder and hand disability scores fell¹⁶.

Progressive overload

The doses trials used

Each trial below reports one set dose^6,7:

Study	Hold and repetitions	How often and how hard
60 young women, standing stretch	30 seconds, in two sets of three	Five days a week for three weeks⁶
Six-week home programme, corner	10 seconds, repeated ten times	As described in a later paper²
7-week trial, wall stretches	Three exercises held without a break for 5 minutes each	Three times a week, kept at the point of discomfort⁷
Eight-week home study, band stretches	Three exercises of 5 minutes, with 30 seconds of rest between	15 minutes a session, at 6 to 7 on a stretching intensity scale²⁴

The authors of the eight-week home study noted that it did not report on possible long-term problems from overstretching the shoulder joint²⁴. They wrote that such problems might occur if intensity or duration were increased²⁴.

What changing the dose did

Two experiments measured the shear modulus of the pectoralis minor, a measure of tissue stiffness from ultrasound²⁶. In 20 people, it fell by 2.3 kPa after one 30-second stretch and by a further 1.0 kPa after three²⁶. In 16 people stretched by physiotherapists, ten 30-second stretches kept it lower for the 15 minutes measured afterwards²⁶. After a single 30-second stretch, the decrease was seen straight afterwards and no later²⁶.

One meta-analysis of static stretching programmes, across muscle groups, found larger flexibility gains with more time under stretch²⁷. Another, of 77 stretch-training studies, found no relationship between range gained and total stretch duration or weekly frequency²⁸.

Connections

The muscles it stretches

In 50 people without shoulder disorders, the pectoralis minor was 2.24 cm longer during the one-arm self-stretch¹. In an elastography study of 15 men, horizontal abduction positions most lengthened the clavicular and abdominal parts of the pectoralis major¹².

The shoulder blade

A review reported that chest stretching, alone or with strengthening, can alter the resting position of the scapula in people with abducted shoulder blades¹⁹. In the trial of 60 young women, adding lower trapezius strengthening changed rounded shoulder posture more than stretching alone⁶.

In 63 recreational participants, eight weeks of pectoral stretching raised bench press strength compared with controls²⁹. A 6-week programme for 44 college swimmers paired a corner stretch with a sleeper stretch and tubing exercises³⁰. It produced no significant differences between groups in strength or scapular motion³⁰.