WO2018029177A1

WO2018029177A1 - Sports bra and shirt

Info

Publication number: WO2018029177A1
Application number: PCT/EP2017/070033
Authority: WO
Inventors: Leonie Catharina Elisabeth VAN DEN HEUVEL; Jozef Hubertus GELISSEN; Reinder Haakma
Original assignee: Koninklijke Philips N.V.
Priority date: 2016-08-08
Filing date: 2017-08-08
Publication date: 2018-02-15

Abstract

A sports bra having a front section, a back section, two side sections and two straps is provided. A vital signs sensor is arranged at a first measuring position arranged at the back side and below one of the two straps.

Description

Sports bra and shirt

FIELD OF THE INVENTION

The invention relates to a sports bra and shirt.

BACKGROUND OF THE INVENTION

The online detection of a heart rate of a user by a heart rate monitor during exercise has become very popular. The heart rate of a user can be detected by non-ECG- based heart rate wrist worn monitoring devices which can be based on photoplethysmography (PPG) sensors. The heart rate sensor can also be worn by a chest strap and can communicate the information wirelessly to a wrist worn smart watch.

US 2014/0012145 Al discloses a brassiere having detachable pairs of sensors to detect a heart rate of a user. The sensors are arranged on a flexible band that can be removed from the brassiere. This can however be very cumbersome as a user must always first attach it to the bra before the user can use the bra and the heart rate sensor.

US 2014/0275852 Al discloses a wearable heart rate monitor which can be integrated into or worn in a necklace, a chestband, a bra, an adhesive patch, glasses, or an earring.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a sports bra with an improved heart rate detection capability.

According to an aspect of the invention, a sports bra comprising a front section, a back section, two side sections and two straps are provided. The sports bra furthermore comprises at least one PPG sensor having a light source configured to generate light which is directed towards a skin of a user and a photo detector configured to detect light where said light being indicative of a reflection of light emitted in or from the skin of the user. The sports bra furthermore comprises at least one measuring position, wherein the at least one PPG sensor is placed. A measuring position can be arranged at the back section and adjacent to one of the two side sections. This measuring position covers a latissimus dorsi muscle of a user when the sports bra is worn. According to an aspect of the invention, a further measuring position is arranged at the back section and below one of the two straps. This measuring position covers an infraspinatus muscle or trapezius muscle of a user when the sports bra is worn.

According to a further aspect of the invention, the sports bra comprises a chest strap, wherein at least one PPG sensor is arranged in the area of the chest strap.

According to a further aspect of the invention, at least one PPG sensor is embedded in the fabric of the sports bra.

According to a further aspect of the invention, a shirt having a front section, a back section, two side sections, two straps and at least one PPG sensor is provided. The shirt furthermore comprises at least one measuring position where the at least one PPG sensor is placed. A measuring position is arranged at the back section and adjacent to one of the two side sections. This measuring position covers a latissimus dorsi muscle of a user when the sports bra is worn.

The bra or shirt according to an aspect of the invention is advantageous over a wrist worn smart watch as the wrist location is very volatile to motion artifacts and therefore the chest location is a better location for the sensor position. Additionally, when a wrist worn device is not allowed (certain sports) or is not possible or not desired (swimming), the chest is more interesting for the sensor position.

According to a further aspect of the invention, an undergarment is provided with at least one PPG sensor as described above.

According to an aspect of the invention, a method of detecting vital signs of a user using at least one vital signs sensor is provided. The user wears a sports bra or a shirt. The sports bra or the shirt comprises at least one of a first and second measuring position where a vital signs sensor is positioned at a measuring position. The measuring position covers a latissimus dorsi muscle of a user when the sports bra or the shirt is worn.

According to an aspect of the invention, the best measuring points to detect vital signs of a user, when a vital signs sensor is embedded in a sports bra, should avoid a concave curvature as the vital signs sensor can easily use skin contact. Furthermore, a measuring point with pointy bone structures underneath are also not desirable as the bones may reflect light and as such a position may not be considered as comfortable. Furthermore, motion positions should be avoided which are prone to motion artefacts, for example because of a muscle motion underneath the skin or due to skin rubbing.

In view of these considerations, the first measuring point according to an aspect of the invention is arranged at the latissimus dorsi muscle of a user. This measuring position allows the best measurements of vital signs by means of an optical vital signs sensor from the physiological point of view.

A further aspect of the invention covers the use of a sports bra comprising a front section, a back section, two side sections, two straps and at least one vital signs sensor having at least one PPG sensor to detect vital signs of a wearer, wherein at least one measuring position is provided where the at least one vital signs sensor is placed, wherein a measuring position is arranged at the back section, adjacent to one of the side sections and wherein this measuring position covers the latissimus dorsi muscle of a user when the sports bra is worn.

It shall be understood that a preferred embodiment of the present invention can also be a combination of the dependent claims or above embodiments or aspects with respective independent claims.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following drawings:

Fig. 1 shows a schematic representation of a vital signs sensor according to the invention,

Fig. 2 shows a picture indicating a back musculature,

Fig. 3 shows a schematic representation of a sports bra according to an aspect of the invention,

Fig. 4 shows a schematic representation of a sports bra according to a further aspect of the invention, and

Fig. 5 shows a schematic representation of the sports bra of Fig. 4.

DETAILED DESCRIPTION OF EMBODIMENTS

The invention relates to a sports bra or a shirt (like an under shirt) with at least one optical heart rate sensor or optical vital signs sensor e.g. in form of a PPG sensor to determine vital signs of a user when the sports bra is worn.

Optical heart rate sensors are well known to monitor or detect vital signs like a heart rate of a user. Such a heart rate sensor can be based on a photoplethysmograph (PPG) sensor and can be used to acquire a volumetric organ measurement. By means of pulse oximeters, changes in light absorption of a human skin are detected and based on these measurements a heart rate or other vital signs of a user can be determined. The PPG sensors comprise a light source like a light emitting diode (LED) which is emitting light into the skin of a user. The emitted light is scattered in the skin and is at least partially absorbed by the blood. Part of the light exits the skin and can be captured by a photo detector. The amount of light that is captured by the photo detector can be an indication of the blood volume inside the skin of a user. A PPG sensor can thus monitor the perfusion of blood in the dermis and subcutaneous tissue of the skin through an absorption measurement at a specific wave length. If the blood volume is changed due to the pulsating heart, the scattered light coming back from the skin of the user is also changing. Therefore, by monitoring the detected light signal by means of the photo detector, a pulse of a user in his skin and thus the heart rate can be determined.

The PPG sensor can be implemented for example in a smart watch and can be placed in direct contact with the skin of the user. If the PPG sensor is, however, not anymore in direct contact with the skin of the user, e.g. if a loss of skin contact has occurred, the output of the photo detector cannot be used to detect vital signs of a user.

Vital signs of a user can be the heart rate and the respiration rate. Fig. 1 shows a basic representation of an operational principle of an optical vital signs sensor. In Fig.l, the optical vital signs sensor, e.g. a heart rate sensor 100, with its contact surface 101 is arranged or placed on for example an arm of a user or against the skin of a user at another location. The contact surface 101 can be (directly) placed onto the skin 1000 of the user. The heart rate sensor 100 comprises at least one light source 110 and at least one photo detector 120. The light source 110 emits light via the contact surface 101 onto or in the skin 1000 of a user. Some of the light is reflected and the reflected light can be detected by the photo detector 120. Some light can be transmitted through tissue of the user and be detected by the photo detector 120. Based on the reflected light, vital signs of a user like a heart rate can be determined by a processing unit 130. The invention relates to the placement or arrangement of PPG sensors in or on the sports bra or a shirt as described in the following:

Fig. 2 shows a picture indicating a back musculature of a user. In Fig. 2, two possible measurement positions namely A, B are depicted. The measurement position A can be arranged between the shoulder blade and the back bone of a user namely in the region of the infraspinatus muscle. A further measurement position B can be arranged below the shoulder blade in particular in the region of the latissimus dorsi muscle. The correct location of the measurement positions of the optical PPG sensors to determine a heart rate or other vital signs of a user is very important to obtain a good signal-to-noise ratio. Furthermore, the measurement positions also affect quite significantly the signal quality and the robustness against motion artefacts. Moreover when choosing the measurement positions it should also be considered that the PPG sensor should not be positioned in a region containing bones as this might be considered as uncomfortable.

Furthermore, it should be considered that during exercise several muscles can contract which can reduce the robustness of the PPG sensor.

According to the invention the preferred measurement positions are over convex muscle portions e.g. position A, B.

The measurement positions A, B has depicted in Fig. 2 are not located on a bone and are located over convex muscles which are not moving a lot during exercise.

Fig. 3 shows a schematic representation of a sports bra 200 having a back section 210, and two straps 220, front section 230 and two side sections 201. Furthermore the bra 200 has at least one first and second position 240, 250, where a PPG sensor 100 (as described above) can be arranged. When the bra 200 is worn by the user, then the position 240 substantially corresponds to the position A and the position 250 substantially

corresponds to the position B as described in Fig. 2. In other words, when the sports bra 200 is worn, the position 240 will cover the position A and the position 250 will cover the position B.

According to the invention, at least one vital signs sensor having at least one PPG sensor 100 will be placed at the first and/or second position 240, 250. These positions are advantages as the fabric of the sports bra is not in friction with the skin of a user.

According to an aspect of the invention, a shirt (like an under shirt) or undergarment is provided with at least one PPG sensor located at corresponding positions as in the sports bra.

Fig. 4 and 5 show a schematic representation of a sports bra according to further aspect of the invention. Fig. 4 shows the front section 230 and Fig. 5 shows the back section 210 of the sports bra 200. The sports bra according to Fig. 4 and Fig. 5 comprises a back section 210, a front section 230 and two straps 220. At the lower end of the sports bra a chest strap 260 is provided. At least one PPG sensor 100 can be arranged at the chest strap 260.

According to a further aspect of the invention the sports bra can have a PPG sensor at the first position 240, at a second position 250 and/or at the chest strap 260. Therefore, the sports bra200 comprises basically three positions, where the PPG sensor can be attached with a respective sports bra.

According to the invention, the PPG sensor comprises LEDs and photodiodes which can be connected in parallel.

According to the further aspect of the invention part of the PPG sensors like the battery and other electronic hardware can be arranged detachably from the LEDs and the photodiodes. A part of the PPG sensor can stay in the sports bra and is arranged watertight so that the sports bra can also be washed. According to an aspect of the invention, a detouchable electronic connection is provided between the LEDs, the photodiodes and the rest of the PPG sensor.

Other variations of the disclosed embodiment can be understood and effected by those skilled in the art in practicing the claimed invention from a study of the drawings, the disclosure and the appended claims.

In the claims, the word "comprising" does not exclude other elements or steps and in the indefinite article "a" or "an" does not exclude a plurality.

A single unit or device may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutual different dependent claims does not indicate that a combination of these measurements cannot be used to advantage. A computer program may be stored/distributed on a suitable medium such as an optical storage medium or a solid state medium, supplied together with or as a part of other hardware, but may also be distributed in other forms such as via the internet or other wired or wireless telecommunication systems.

Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1. Sports bra (200), comprising:

a front section (230),

a back section (210),

two side sections (201),

- two straps (220), and

at least one vital signs sensor (100) having at least one photoplethysmographic (PPG) sensor (100) which comprises a light source (110) configured to generate light which is directed towards a skin (1000) of a user, and a photo detector unit (120) configured to detect light, wherein said light being indicative of a reflection of light emitted in or from the skin (1000) of a user, and

at least one measuring position (240, 250, 260), where the at least one vital signs sensor (100) is placed,

wherein a measuring position (250) is arranged at the back section (201), adjacent to one of the two side sections (201) and covering a latissimus dorsi muscle of a user when the sports bra (200) is worn.

2. A sports bra (200) according to claim 1, wherein a further measuring position (240) is arranged at the back section (210) and below one of the two straps (220) and covering an infraspinatus muscle of a user, when the sports bra (200) is worn.

3. A sports bra (200) according to claim 1, further comprising a chest strap (260) wherein at least one PPG sensor (100) is arranged in the area of the chest strap (260).

4. A sports bra (200) according to claim 1, wherein the at least one PPG sensor (100) is embedded in the fabric of the sports bra (200).

5. A shirt comprising:

a front section (230),

a back section (210), two side sections (201),

two straps (220), and

at least one vital signs sensor (100) having at least one PPG sensor (100) which comprises a light source (110) configured to generate light which is directed towards a skin (1000) of a user, and a photo detector unit (120) configured to detect light, wherein said light being indicate of a reflection of light emitted in or from the skin (1000) of a user, and at least one measuring position (240, 250, 260), where at least one vital signs sensor (100) is placed,

wherein a measuring position (250) is arranged at the back section (201) and adjacent to one of the two side sections (201) and covering a latissimus dorsi muscle of a user when the sports bra (200) is worn.

6. Method of measuring vital signs of a user by a vital signs sensor (100) having at least one PPG sensor (100) which comprises a light source (110) configured to generate light which is directed towards a skin (1000) of a user and a photo detector unit (120) configured to detect light, wherein said light being indicative of a reflection of light emitted in or from the skin (1000) of a user, comprising the steps of:

wearing a sports bra (200) or a shirt,

wherein the sports bra (200) or the shirt comprises at least one vital signs sensor (100) at a measuring position which covers a latissimus dorsi muscle of a user and measuring vital signs of a user wearing the sports bra (200) or the shirt.