Using NIRS to non-invasively monitor muscle oxygenation during exercise

Skeletal muscles are the basis of all movement in the human body, and athletes work years to train their muscles to be powerful yet efficient. Even if a single muscle could allow a person to lift a car, it would not be very useful if the muscle could no longer create forceful contraction again for several hours. The muscle also must be efficient in the use of oxygen, ions, and other substrates that allow for contraction to be able to quickly recover and be prepared for repeated contraction. Muscle oxygenation is particularly important for both endurance and power of a muscle because it is necessary to produce ATP to power muscle cells to contract. Heart rate and blood oxygen delivery are helpful for getting an idea of an athlete’s efficiency, but they do not tell the whole story for the muscle. At the muscle, the balance between delivery and consumption of oxygen explains its efficiency [1]. To measure muscle oxygen saturation, a technique called near-infrared spectroscopy (NIRS) is used to get real time data to inform athletes of the state of their muscles during training. This is a powerful tool for maximizing athletic gains in muscles from training and to see the state of the muscle over time and after rest.

Early NIRS instrumentation was contained to the lab, but recently portable versions have become more common, which is very important for its use in both the medical and research fields. In medicine, NIR has been used for study of septic shock, free tissue transfer, real-time tissue perfusion during surgery, cancer nanotechnology, and peripheral arterial disease.  For this post, the use of NIR in exercise will be highlighted. In exercise, NIRS is a great tool because it is a non-invasive method that can be applied locally to muscles or tissues of interest and provide real time data during exercise. NIRS is highly sensitive to changes in muscle tissue oxygenation [2, 3, 4], and it reflects the balance between oxygen delivery and utilization, unlike measurements of arterial or venous blood samples which have been used previously and are minimally invasive [2]. NIRS works by measuring the percentage of oxygenated hemoglobin to total hemoglobin (oxygenated and deoxygenated hemoglobin) to give muscle oxygenation. Hemoglobin is the main oxygen carrying protein in the blood and can carry 4 oxygen molecules (O2). Oxygenated and deoxygenated hemoglobin scatter NIR light (600-1000 nm) differently, so their relative concentrations can be found from their molecular absorption coefficients. To do this, three to four different wave lengths of light will be used to determine the concentrations of each based on the change in molecular absorption coefficients at different wavelengths (Fig 1). NIR light must be used as it: 1) passes through skin, bone, and most biological tissue, and 2) is the appropriate wavelength where the small amount of absorption that occurs is predominately from hemoglobin (Fig 2) [5].  As the muscle performs work, the muscle oxygenation will decrease as a function of the work and the training of the muscle.

Fig. 1: Molecular Absorption Coefficient Profiles for Oxygenated and Deoxygenated Hemoglobin [5]

Fig 2: Light Absorption by Wavelength [5]

 

 

 

 

 

 

 

 

 

 

A patent on google patent claims to leverage this technology in a wearable article of clothing for athletes to be able to measure muscle oxygenation real-time (Fig 3) [6]. The patent claims to be a method and apparatus for assessing tissue oxygenation saturation through two main claims that summarize to: a portable apparatus that is a wearable article capable of measuring oxygenation saturation of at least one of a skin dermis layer, adipose layer, or muscular fascial layer of a user during physical activity using at least one near-infrared spectroscopy probe including at least one near-infrared light source and at least one photodetector. In short, the patent is a claim on a portable, wearable NIRS device for tissue oxygenation levels. NIRS has been a research method for decades, so the novel part of this patent lies in the incorporation of this technology into a wearable article of clothing.

Fig 3: Figure from patent illustrating wearable shirt, shorts, and socks using NIRS

Fig4: Figures from patent showing example data of muscle oxygenation average during constant rate running at different grades (top) and real time data from medial gastrocnemius muscle during weighted exercise and unweighted control (bottom)

This patent pertains primarily to the measurement of tissue during exercise (Fig 4). This could be of use for athletes during training to be able to compare what levels of exercise cause certain levels of muscle oxygen saturation loss. For example, highly trained athletes often train at high altitude to reduce oxygen in the air so that their body adapts to becoming more efficient with oxygen usage. This prompts higher performance when returning to normal oxygen levels. Using NIRS could allow them to find a training regime that caused the same hypoxia in muscle without traveling to higher altitude (they will still miss out on some of the pulmonary and cardio vascular advantages that training at altitude can produce). This may also be helpful in rehabilitation as the change in muscle oxygenation is an indicator that the muscle is being used and can inform physical therapists if the patient is engaging the correct muscles during rehab. Additionally, the device may also have merit in the medical realm for monitor muscle oxygenation in patients with chronic heart failure, peripheral vascular disease, chronic obstructive pulmonary disease, and varying muscle diseases [3, 4].

  1. Patent title: Method and apparatus for assessing tissue oxygenation saturation
  2. Patent number: US20170273609A1
  3. Patent filing date: 2017-03-22
  4. Patent issue date: Patent Pending
  5. How long it took for this patent to issue: TBD
  6. Inventor(s): Luke G. Gutwein, Clinton D. Bahler, Anthony S. Kaleth
  7. Assignee (if applicable): Indiana University Research and Technology Corp
  8. U.S. classification: A61B5/0075
  9. How many claims: 20

References and Further Reading

[1] BSX Athletics https://support.bsxinsight.com/hc/en-us/articles/204468695-What-is-muscle-oxygenation-

[2] Bhambhani, Y. N. (2004). Muscle Oxygenation Trends During Dynamic Exercise Measured by Near Infrared Spectroscopy. Can. J. Appl. Physiol., 29(4), 504–523.

[3] Hamaoka, T., Mccully, K. K., Quarisma, V., Yamamoto, K., & Chance, B. (2007). Near-infrared spectroscopy / imaging for monitoring muscle oxygenation and oxidative metabolism. Jounal of Biomedical Optics, 12(6), 1–16. http://doi.org/10.1117/1.2805437

[4] Boushel, R., & Piantadosi, C. A. (2000). Near-infrared spectroscopy for monitoring muscle oxygenation. Acta Physiol Scand, 168, 615–622. http://doi.org/10.1046/j.1365-201x.2000.00713.x

[5] Shimadzu Commercial Website https://www.ssi.shimadzu.com/products/imaging/labnirs-principle-of-operation.html

[6] Patent https://patents.google.com/patent/US20170273609A1/en?oq=US20170273609A1

[7] Ferrari, M., Muthalib, Makii, & Quarisma, V. (2011). The use of near-infrared spectroscopy in understanding skeletal muscle physiology : Phil. Trans. R. Soc. A, 369, 4577–4590. http://doi.org/10.1098/rsta.2011.0230 

[8] Artinis Commercial Site https://www.artinis.com/portamon#portamon-software

Air Displacement Plethysmography: How It Works Patent Post

Body Fat is an important health statistic. Whether you are a person who dreams of obtaining “rock-hard” abs on the beach, a person aiming to shed a couple of pounds for the new year, a doctor assessing a patient’s risk of cardiac arrest, or just a general fitness enthusiast, body fat is the rave of today’s exercise culture. Although there is a negative connotation associated with body fat, it is an essential nutrient. Fats are needed to boost energy levels and numerous metabolic processes. Generally, a healthy individual is considered to have a body fat value in the range of 18-25%. However, excessive fat levels have shown a positive correlation with mortality.

Historically, body mass index (BMI) has been used more often by doctors to evaluate a person’s overall fitness. But a health study in the American Journal of Clinical Nutrition determined that an individual’s body fat is more effective in assessing his/her risk of developing chronic disease than BMI due to the failure of the latter in differentiating between fat-free mass (bone, water, lean tissue) and the weight of fat mass in the body. An individual may be on the lower end of the obesity spectrum in terms of total weight, but still possess an enormous risk of cardiovascular diseases due to having too much body fat.

Based on these facts, one could argue that healthcare professionals should deviate from the practice of collecting patient’s BMIs and focus their attention solely on calculating patients’ body fat percentage. However, measuring an individual’s  body fat is an arduous process due to the amount of time need to procure data and make calculations, which require a good understanding of topics such as calculus. and conversation of mass (nasty math/physics). For that reason, BMI  is more commonly used despite the lower confidence in this data. Thus, there is a high demand for technology that can assess an individual’s body fat percentage in an accurate and timely manner.

Air Displacement Plethysmography is an emerging technology that utilizes air perturbations that occur when a subject enters a confined space in order to determine their body fat levels. Please click here to view figures collected from a US patent filed for the BodPod: an air plethysmographic apparatus manufactured by Life Measurements Instruments, a medical device company based in Concord, California.

The Bod Pod consists of an air circulation system (represented by item 60 on figure 2) linked to a plethysmographic measurement chamber (pointed out by item  50 on figure 2). The air circulation system (embodied in greater detail by  Fig 3 of the patent), comprised of one or more pumps, acts as both a source of circulation and filtration within the chamber by using ambient air (air that is derived from a temperature-enclosed environment). Clean air is pumped into the chamber via an inlet tube (represented by item  86) while contaminated air is moved out of the chamber through an outlet tube (represented by item 88), where it is later filtered and recycled. The result is a clean and controlled air environment that is maintained throughout the duration of the BodPod’s operation. Inside of the Bod Pod are plethysmographic measurement components(represented by item 56 and 58 on Figure 2) that record perturbations in the volume of air inside the chamber before and after a subject enters in order to calculate the subject’s body volume by subtraction. For those who aren’t familiar, a plethysmograph is an instrument that measures displacements in a fluid within an enclosed environment (in this case, the BodPod chamber). In order to gather accurate data, it is imperative that the volume of air in the chamber is recorded before a subject enters the chamber. Once all data has been collected, it is wirelessly  transmitted to a computer for further analysis using software provided by Life Instruments. Once the subject’s body volume has been determined, it is immediately inserted into Siri’s Equation to calculate the subject’s body fat percentage.

 

References

Dempster Phillip, Michael Homer, and Mark Lowe (2004). United States Patent 20040193074 A1. Retrieved from https://patentimages.storage.googleapis.com/93/cf/ea/6d2d1346ea1129/US20040193074A1.pdf

 

Body Composition Testing for All

Patent Number: US 6,631,292 B1

Filing Date: March 23, 2001

Issue Date: October 7, 2003

Inventor(s):  Rudolph J. Liedtke (Grosse Pointe Park, MI)

Assignee: RJL Systems, Inc. (Mt. Clemens, MI)

U.S. Classification: 600/547

Claims: 20

                                                               

Figure 1. A functional block diagram of a single aspect of a device based on the invention

 

A bioelectrical impedance analyzer is an apparatus used to determine bioelectrical impedance measurements. This particular analyzer is used to measure a particular area of impedance in a subject. This works by having a constant source of current where the currents input is controlled by a feedback loop. This feedback loop uses an error signal that represents the difference between the actual impedance of the area measured, the target current. The analyzer also contains an impedance measuring circuit that detects and output voltage from the area of the subject. This circuit splits the measured output voltage into a reactance output signal and a resistance output signal. The image above shows a block diagram of the electrical components within this analyzer.

Bioelectrical impedance analyzers can be used to find measurements within the human body. These measurements    can then be used to determine many different things about the body being tested. Using these measurements, blood flow, cardiac output, lean body mass, and body fat can be found for the tested individual. This invention of the bioelectrical impedance analyzer differs from those before it because it separates the electrical components of the analyzer from the individual using it. This is different from previous designs that directly attached electrodes to the individual. Another difference in this invention its temperature insensitivity. This allows the analyzer to be easily portable compared to its related technologies.

This analyzer invention had 20 claims outlining the main components of this device. These claims all referred to the electrical components of the analyzer. The main claims of this invention are that the constant current sources input current is controlled by an internal feedback loop that uses error signals to calculate an output. Another main claim is that the impedance measuring circuit is made to give out both a reactance and a resistance output signal.

This particular bioelectrical impedance analyzer invention would be ideal for any individual who is concerned about their body composition. It is easily portable and safe to use. For example, an individual who is looking to cut body fat, but doesn’t want to pay for the expensive body fat testing, would benefit from this analyzer. This analyzer would also be good for people who are body builders that travel often. This way they would have a way to test their body composition so that they could stay on track with their goals. Having had personal experience using a portable bioelectrical impedance analyzer, I think this would be ideal for someone wanting a close estimate on different body composition measurements. Even though the measurements aren’t as accurate as some other more expensive and invasive techniques, these portable analyzers work great and are more easily accessible. It is interesting to think about how this analyzer will advance and become more accurate in the future.

Reference

Liedtke, Rudolph J. (2003). United States Patent No. US6,631,292B1. Retrieved

from https://patents.google.com/patent/US6631292B1/en

Just Trying To Reach 10,000 Or Competing To Step Above The Rest – How Do Wrist Pedometers Count Our Steps?

People everywhere are getting their steps in. Whether they’re attempting to reach 10,000 steps a day or participating in competitions with friends, family, or coworkers to see who can step the most, people are moving – and they want to know exactly how much. Wrist fitness trackers with built in pedometers have become a popular mode for individuals to track their daily activity, but how do these devices work?

Let’s look at Apple Incorporated’s Wrist Pedometer Step Detection technology. This technology uses motion data to determine a force comparison threshold that can be used to accurately count steps while a user is running and walking.

An illustration of a person using a wrist pedometer for step detection, included in United States Patent No. US20140074431A1

 

Patent title: Wrist Pedometer Step Detection

Patent number: US20140074431A1

Patent filing date: 2012-09-10

Patent issue date: 2014-03-13

Inventor: Yash Rohit Modi

Assignee: Apple Inc

U.S. classification: G01C22/006 Pedometers

How many claims: 18

Forces acting on a wrist pedometer can be associated with user movement, specifically when they’re walking or running. The force of gravity as well as the forces exerted by the user against the force of gravity are measured by the pedometer; changes in forces acting on the device can be used to determine step count as well as type of exercise. While standing the force detected by the pedometer is 1G (one times the force of gravity). When a user is pushing against the ground to step forward the force detected by the pedometer can rise above 1G, and while the user is between steps the force detected by the pedometer can go below 1G. The pedometer can detect when a user takes a step by monitoring forces and determining when the 1G threshold is crossed.

Forces are compared based off magnitude and frequency to accurately count user steps. Other pedometer technologies worn at the trunk have used a 0.2G comparison threshold to account for steps, meaning when the pedometer experiences a for change of at least 0.2G one step will be added onto the step count. This threshold has been set to prevent noise and standing movements from being accounted for in step count.  However, the force differential experienced by wrist pedometers change with alternating steps. With the step on the side opposing the pedometer, the force acting on the pedometer is often less than 0.2G and may not be detected by the device with this threshold in place. To overcome this issue, this devices step algorithm has included frequency of threshold crossing to account for opposing steps. If the comparison threshold has been crossed twice over a set step time, then the technology will account for two steps rather than one. This prevents the technology from missing steps – thus, increasing device accuracy.

Motion data is also utilized in this technology to account for user activity and adjust parameters appropriately count steps . Fast Fourier Transform (FFT) is used to determine dominant frequency of motion and determine user activity. If the dominant frequency is below run threshold, then steps are counted for within walking parameters, described above. If the dominant frequency is above run threshold, then steps are counted for within running parameters. While running, there is a reduction in change of force acting on the pedometer; the change of parameters takes this into account and utilizes this information to properly account for steps.

Unlike other step counting technologies on the market, this product has improved accuracy in step count. The step counting algorithm has parameters that better define noise and non-walking movement as well as a mode to account for the imbalance in force acting on the wrist pedometer during walking. Less steps are unaccounted for and less random movements are counted – making for more accurate step counts.

There are a number of pedometer technologies that exist on the market today. Regardless of brand and step counting algorithm – these technologies are giving indiviudals the ability to count their steps and measure their fitness levels, promoting an active lifestyle for those who utilize them.

Reference

Modi, Yash Rohit. (2014). United States Patent No. US20140074431A1. Retrieved from https://patents.google.com/patent/US20140074431A1/en

Patent Blog Post: Fitbit’s Wearable Heart Rate Monitor

Perhaps you’ve been barraged by emails from Fitbit that try and get you to buy one of their products during one of their many sales. Perhaps you’re a trendy techie and have a wearable in the form of a Galaxy or Apple Watch. Or perhaps you’re simply the owner of a smartphone made within the past few years. All these technologies have heart rate monitoring built into them from the get-go, and it is increasingly hard to get away from gadgets that don’t have some form of heart monitoring. With how ubiquitous the technology has gotten, I would like to look today at one of the patents put forward by Fitbit, one of the more popular brands when it comes to wearable fitness trackers. For this post, I’ll be using the information put forward by Google Patents, seen here.

One of the many figures in the patent, detailing the backside of the wearable.

The patent is simply titled as, “Wearable heart rate monitor,” and has a patent number of US8945017B2. It was originally filed on June 3rd, 2014, and was then approved on February 3rd, 2015. This makes the time to issue a little under a year, which is quite fast for an electronics product. The two inventors credited in the patent are Subramaniam Venkatraman and Shelten Gee Jao Yuen. Looking at the other patents associated with them, Venkatraman seems to have worked on more navigational devices, while Jao Yuen has worked on several other gyroscope-related projects. The assignee is, of course, Fitbit Inc. themselves. Officially, one of the classifications of the patent is, “signal processing specially adapted for physiological signals or for diagnostic purposes for noise prevention, reduction or removal.” This one patent has 30 different claims to its name.

Of the 30 different claims in the patent, many of them tie into 2 main claims. The first is that the wearable heart monitor has a way to efficiently, accurately, and quickly determine the heart rate of the user. The second is to ensure that the wearable is capable of compiling the heart rate monitor’s data, including the heart rate data. This patent is aimed at both casual and advanced fitness enthusiasts, as the data gleaned from the wearable is handy to track. Runners, in particular, would find this tempting as it also mentions step tracking and other forms of movement.

The heart rate monitor works by using a waveform sensor, which reads signals at the surface of the skin. These signals are sent to the rest of the device, where the data is processed. The raw data from the sensor is rough and has a lot of noise from several factors, including movement and moisture. To remove the noise, the data has to be passed through several filters. From that data, a heart rate can be determined, and then presented to the user. Unlike the monitors of prior ages, this heart rate monitor would not rely upon disposable components, instead simply being able to be used multiple times by wearing it. In addition, the heart rate tracker would track more than just heart rate, including details about steps.

References:

Venkatraman, S., & Yuen, S. G. J. (2014). Wearable heart rate monitor. Retrieved from https://patents.google.com/patent/US8945017B2/en

Blood Pressure and Heart Rate Measuring Watch

Patent title: Blood pressure and heart rate measuring watch

Patent number: US06084961

Patent filing date: 1979-10-15

Patent issue date: 1982-05-25

Inventor(s):Ronald L. Broadwater Russell R. Haynes Samah A. Mitry

Assignee (if applicable): TECH ENGR AND DESIGN

U.S. classification:  G04G21/025

Claims: 16

Figure 1. This figure shows the watch itself and the sensor on the watch band part.

Summary:

This invention is a portable blood pressure and heart rate monitoring device that is in a wrist watch format. Blood pressure and heart rate signal is measured by the sensor on the watch that attached to wrist when it’s wear by patient. This wrist can measure systolic and diastolic pressure and heart accurately and quickly, as well as tell time. In addition, with this compact format, patient can wear it in many circumstances and operate it without lots of professional knowledge.

People who like to do exercise and elder people might be interested in this invention.  people who do exercise often might want to know there heart rate in order to control their heart rate in a certain range, so that their exercise effect can be the most ideal for them. For elder people who potentially or actually have heart problems, a portable heart rate and blood pressure monitor like this invention would be ideal for them to monitor their heart condition, so that they can find treatment before the condition become worse.

In order to achieve the monitoring function, a piezoelectric transducer is placed on the watch band. when patient wear it, the transducer attach the radial artery,and it will generate electrical pressure impulse which correspond to the magnitude of blood pressure. The highest impulse is recognized as systolic impulse, and the lowest impulse is recognized as diastolic impulse. Also, a time counter is employed to measure the heart rate. There are also some prior art of this type health monitor. For example, US. Pat. No. 3’807’388. with this device, heart rate is measured by counting heart beat in a known frequency, and the heart beat is then related a particular average heart rate. Since that device does not measure the heart rate directly, it can be somewhat inaccurate.

I choose this patent because smart watch is currently a popular wearable health product, and it’s getting more and more developed. I am surprised that this patent was issued in 1979 which is about 40 years before. It seems this type compact wearable technology is now more commonly accepted by customers. The concept to bring convince of health monitoring from hospital to everyone’s side is a kind of evolution of medical system.

WRIST EXERCISE DEVICE

Patent title: Wrist exercise device

Patent number: US3924851 A

Patent filing date: Oct 25, 1974

Patent issue date: Dec 9, 1975

Inventor(s): Winston Herbert

Assignee (if applicable): Winston Herbert

U.S. classification:  482/105

Claims: 1

FIG. 1 is a perspective view illustrating the

exercise device in its wrist-encircling position;

FIG. 2 illustrating the

inside surface thereof, i.e. the surface against the user’s

wrist, and

FIG. 3 the outside surface; and

FIG. 4 is an end elevational view showing details of

the device in its wrist~encircling condition.

FIG. 5 is a perspective view of another embodiment

of the wrist exercise device hereof.

The wrist exercise device is generally a wrist band that is comfortable to wear. It consists of 2 parts, fabric body and metal rods as weights. The weight of the device is adjustable by adding or removing metal rods on the band. It also can be wear around the ankles and it is easy to make exercise more strenuous.

This invention could be used by anyone that wish to add some intensity to their exercise; also, it could be used to help patients accomplish recovery training.

While wearing this product on the end of limbs, depends on how much weight the user loads, it could help the user build muscle by lifting extra weight. For patients, it could be used while passive training by helping them stretch muscle groups or joints; also, it can be used as extra weight for patient to do active exercise.

Comparing to traditional free weights, this device is designed wearing on limbs, so it does not require users to constantly using hands to hold it. Also, it is comfortable to wear, portable, and adjustable.

The reason that I chose this patent is that this wrist exercise device is simple; however, it is has many advantages comparing to traditional free weights which are extremely easy to use, more portable, adjustable, and it could be used almost every class of people.

Just Keep Swimming (and checking your heart rate)

While exercise monitoring devices are made to deal with moisture and sweat, have you ever wondered how professional swimmers monitor their exercise while submerged? During the presentation on elevation masks in class I became intrigued about how complex it would be to monitor exercise in the water. This thought led me to the discovery of a swimming heart rate monitor in the form of a chest strap. Waterproof watches and dive computers that can also track heart rates exist on the market, however chest straps are known to provide a more accurate reading due to the proximity to the heart. But how could this design stay on, stay dry, and maintain accuracy? Let’s look into it.

Patent Title: Swimming Heart Rate Monitor
Patent Number: US20140336493 A1
Patent Filing Date: May 8, 2014
Patent Issue Date: Nov 13, 2014
Length for patent to issue: ~6 months
Inventors: Christopher J. Kulach, Timothy Vandermeiden, James K. Rooney, Rogelio A. Rivas, Phillip J.C. Spanswick
Assignee: Garmin Switzerland Gmbh
U.S. Classification: 600/390 (Belt or strap)
How Many Claims: 20

Figure 1. Front perspective view of swimming heart monitor containing electronics module at point 22 and length adjusting mechanisms at point 40.

The device shown in Figure 1 is comprised of two electrodes, two electrical connectors, an electronics module, and a water sealing feature. The adjustable strap, to be worn on the upper torso, is specifically designed to maintain function in chlorinated water, salt water, throughout intense body movement at high pressures. The electronic module processes electrical activity generated by the heart beat which is picked up by the electrodes. The electrical connectors on the external surface of the strap link the module to the electrodes. The connectors are enclosed by a water sealing feature, and attached to the removable electronic module which is in its own watertight housing. This module can be removed from the water-proof strap and used with other straps, in or out of water. This provides users with flexibility at a low cost. The user can monitor the heart rate in real time or upon completion of the exercise.

Figure 2. View of the module coupler and housing which are located on the external surface of the strap.

The strap itself, in length, is one third fabric elastic material and two thirds inelastic material, such as polyester, and is adjustable in length. The inelastic section is coated with a material, such as silicone, to increase the coefficient of static friction and prevent water flow between the skin and strap. The device creates a barrier from water, which would attenuate the amplitude of the heart signal, using two O-rings axially positioned on a post of the electrical connector. The electronics module is held in place by the coupler in Figure 2, also sealed by a water-proof housing.  Electrically conductive materials, such as conductive thermoplastic polyurethane (CTPU) or conductive silicone is used for the electrodes in order to maintain flexibility so contact with the skin remains constant. The module is to be placed around the sternum, with each electrode on either side. More electrodes could also be added to measure galvanic skin response, which tells the user information about hydration levels. The electronic connectors consist of a cylindrical post that attaches to an interlocking mechanism on the electronics module. The connectors also contain a first and second contact, which include an electrically conductive pin made from steel or copper that connects to the electronic component of the module. To combat skin impedance, filtering techniques such as the Lease-Means Square Algorithm are used to calculate the heart rate. The electronic module contains a battery, signal amplifiers, processing elements, memory elements, transmitters, and antennas that allow the data to be communicated in several ways. Certain models may also contain inertial sensors such as accelerometers or gyroscopes, so the device can be personalized to the user’s needs.

This patent referred to wrist monitors, headbands, and belts with similar capabilities, some for aquatic use and some for land. It is ideal out of this group of ideas because of its proximity to the heart which typically results in more accurate signals. Compared to other chest straps, it is ideal for aquatic environments because of the proportions of elasticity of the strap. This provides a snugness that is designed not to fold on itself or slip away from the heart when wet, and the materials for the electrodes are designed similarly. I found it particularly impressive that the device is multifunctional and adaptable beyond heart rate monitoring.

Physical therapy clinics would be a great target audience because of this, as they could buy a few different models and adapt per patient as necessary, saving them both money and space. This technology is also useful for competitive swimmers and triathletes. For those training, it allows them to reach their specific training goals, whether they want to hit the recovery, aerobic, or lactate threshold training zone. For those in rehab, where a physical therapist might want to ensure they are not surpassing a certain heart rate, this device would be ideal and potentially more accurate than a heart rate monitor worn on the risk. My question about underwater exercise monitoring was answered by this patent as well as the other related products that are being developed, and it’s interesting to think about what this kind of technology might lead to in the future of rehab and water-sports.

Get Shredded Easily, As Seen on TV

Patent title: Wheeled Exercise Device

Patent number: US 20120157274 A1

Patent filing date: December 16, 2011

Patent issue date: April 21, 2015

How long it took for this patent to issue: 3 years, 4 months

Inventors: Ian MacColl, Tylor Garland, Jayson Pegler, George Clark, Alden Mills

Assignee: Implus Footcare, LLC (Durham, NC)

US Classification: 482/132

How Many Claims: 10

We’ve all seen them, at least briefly before flipping channels – the exercise equipment infomercials with chiseled models using the latest and greatest workout invention to “tone”, “flatten”, “sculpt”, and “shred” their bodies into perfection. Some are commercial successes that facilitate good workouts, like the Iron Gym … and some are the Shake Weight.  Ab rollers, such as the Perfect Fitness Ab Carver Pro (hereafter referred to as the ACP), tend to fall in the former category.

An ab wheel is an exercise device that, in its most basic form, consists of a wheel with handles on either side. One uses it to strengthen their core (rectus abdominis, internal and external obliques, transverse abdominis, and to a lesser extent, the muscles of the lower back) by kneeling with hands grasping the handles and rolling the wheel forward, maintaining a straight spine as the shoulders move into flexion, and then rolling the wheel back towards the body, bringing the shoulders back in extension. It is a demanding and effective movement for building abdominal strength because of its nature as an anti-extension stability exercise, which strengthens the spine’s ability to resist hyperextension. The basic ab wheel is both effective and ubiquitous, and several variations had already been brought to market; yet, the inventors of the Ab Carver Pro sought to design a unique and superior product.

Figure 1. A general view of the Ab Carver Pro

As it is an improvement upon existing products, the ACP’s claims cannot be separated from comparisons to its predecessors in the art. The most prominent is the Ab Slide, which, encased by plastic housing, has a series of wheels and internal coils that provide a resistive force moving forward and a restoring, or assistive, force moving backward. The problem suggested, though, is that with this and other similar products, either the user is required to hold the handles firmly against the restored turning force, or the restoring force is transmitted through gears that reduce its effectiveness. The ACP claims a mechanism that provides this resistive and restorative force in an optimized way with the internal spring (carbon steel!) attached between an inner surface of the wheel and and the central axle within the interior cavity (Figure 2). There exist interior ribs to prevent coil misalignment.

Figure 2. The internal coil mechanism that provides resistive and restorative forces during exercise

The ACP also claims its “tire overmold” and wide surface, giving it more stability and safety than previous products. The edges of the “tire” are also angled to allow for stable “carving”, or rolling out to either side to engage different muscles to greater intensity (the obliques, as well as the glutes and deltoids, of the side being rolled towards). Rather than the perpendicular, uncontoured handles of its predessecors, the ACP claims its ergonomically designed handles, sloped downward “like a pilot’s steering mechanism” and ending in a slip-preventing ridge. Inventor Alden Mills explains in a video on the product’s website that they did a university study to prove the handle design’s engagement of the triceps muscles, and it showed engagement on the level of a triceps extension, making this not only a core workout but an arm one too. The handle is also designed to reduce stress on the wrists and shoulders.  The patent filed encompasses other versions of the product with bells whistles which are not part of the commercially available product, including one or multiple clutches to engage and disengage different levels of resistance, an electronics module with microchip/microprocessor and LCD display to convey workout data such as distance and repetitions, and a knee pad accessory.

I thought to research this patent because one day I came home from college and the Ab Carver Pro lay on my living room floor (my dad received it free through some rewards-program catalogue).  I did not know about the resistive/restorative coil before I used it for the first time, and I found the feature quite effective. Effective enough, in fact, as to render the device a less effective option for those with moderately to well-developed abdominal strength than a basic ab wheel. Thinking in retrospect, I also did not notice a marked increase in triceps activation and would like to see the claimed “university study” proving this myself. Furthermore, the handle design did not make my wrists and shoulders sing in relief – it simply looked nice and apparently offers a marketing angle. However, it would be worthwhile to gather other people’s opinions on the product, and in its elementary function as an ab wheel, it is a successful product, one that can effectively be used to “tone” and “sculpt” the abdominal muscles as advertised.

Office Gym Exercise Kit to Facilitate Exercise

Patent Title: Office Gym Exercise Kit

Patent number: US 7,137,935 B2

Patent filing date: April 20, 2004

Patent issue date: November 21, 2006

How long it took for this patent to issue: ~1.5 years

Inventor(s): Raymond Clarke, Lorri Wilson-Clarke

Assignee (if applicable):Raymond Clarke, Lorri Wilson-Clarke

U.S. classification: 482/123

How many claims: 9

The Office Gym Exercise kit is a an exercise kit that can be attached to multiple different chairs in order to provide exercises to the user. The kit comes with a flexible body that can be wrapped around the post of a chair in order to “ground” the system. In addition, it comes with an elastic band, two elastic straps, an ankle attachment, various attachable handles, and a means of latching the system to the chair. The kit is shown set up and in use in Figure 1 below. In addition to the contents of the kit, the major claims of this patent highlight the materials that each of these components contain and how to use them. For example, claim 7 explains that the strips provided are nylon and claim 6 explains that the plurality of retainers are D-rings.

I think this technology would be very applicable to all of the working citizens with desk jobs. A major issue that companies face with their employees is the health risk of sitting in a chair all day. After working at a desk job for an internship this summer, the company sent around an Ergonomics expert to analyze our posture and computer placement to make sure that our set up wasn’t causing any pain to us as we worked. In addition, they recommended that we get up and walk around ever hour or so to get moving and take a break from starting at a computer screen. This can help prevent blood clots and keep your energy up throughout the day. Therefore, this technology provides an alternative by having a kit that is attachable to your chair to provide exercise throughout the day. Employees would be able to take breaks, use different body parts for different movements, and be somewhat active throughout the day.

The exercise kit functions by attaching a flexible body to the post of a chair with elastic straps in order to provide tension to the system. Due to the flexibility of the body material, this apparatus can be applied to a multitude of chairs In addition, a back attachment is provided in order to circle around the chair and lock the provided elastic straps to the base of the chair. The elastic straps are connected to a retainer through a latching system to provide a tight grip on the chair. The retainer provides various points of attachment  depending on how long they need the elastic strap to be. Therefore, the user is then able to exercise their arms, legs, and back by pulling on the straps and providing resistance to their muscles. Each of the elastic straps has a D-ring attached for easy grip and handling.

There have been similar patents in the past with this idea, however they all differ from this specific patent slightly. For example, Patent No. 5,690,594 issued in 1997 describes a similar apparatus that can be attached to a chair. However, this patent includes a foot support bar to allow users to extend their foot along the bar. In addition, wheels are mounted to the food support and the user is able to push the foot support bar away from the user and back in order to exercise. In addition, Patent No. 5,599,260 issued in 1997 covers an exercise kit that attaches a roller to the post of a chair via an elastic material. This way, the device can exercise the user by with either their foot or their arm depending on where they attach the element. Furthermore, Patent No. 6,099,445 issued in 2000 describes an exercise device that includes a rigid framed with elements that can be attached to it. The frame can be attached to the central back of a chair and allow the user to exercise their arms, legs, and neck. Therefore, although there are similar patents on the market, there are slight differences between each of them that distinguish their patents from each other.

This patent caught my eye as it is a simple idea that has yet to be implemented into any office that I have heard of. As I mentioned previously, I have experience working a desk job in which they warn you about the lack of movement throughout the day if you do not get up and walk around every now and again. This is a risk to both employees and a company who provides health insure to their employees. Therefore, I figured this kit is an interesting initiative to increase fitness motivation throughout an office environment. In addition, the components that make up this kit are not technology heavy. They are made of normal exercise equipment materials that can most likely be provided at a fairly reasonable price for companies.

Figure 1.) This image shows the kit set up to a desk chair, as described, and in use.