GB2187554A - An exercise machine - Google Patents

Abstract

An exercise machine for human beings includes a member to be operated by a user (U) and load means (M) supplying a variable resistive force to resist operation of the member. A detector (A) monitors a physiological parameter, preferably pulse rate, of the user (U), which parameter alters in accordance with the degree of physical power applied to the operating member by the user. Control means (D) controls the load means (M) automatically in accordance with output from the detector (A) to thereby regulate the resistive force applied to the operating member. Preferably, the resistive force is varied in a time dependent manner subject. The user is monitored constantly and the level of exercise varied accordingly so as to ensure safety and optimum level of exercise. If the output from the detector does not remain within a range determined by the control means the exercise is terminated. <IMAGE>

Description

SPECIFICATION An exercise machine The present invention relates to an exercise machine for human beings.

Many different apparatus are known for assisting people to gain physical exercise. Most of the apparatus are designed to enable the mechanical work done by the user to be varied. This is often achieved by the user adding or subtracting weights or, in apparatus such as exercise bikes, by increasing or decreasing friction acting on a component driven by the user. The known apparatus often include timing mechanisms which sound an alarm when a pre-set period of time has expired. This helps to provide some regulation of the amount of exercise undertaken. However, the user has to select the level of mechanical work to be performed and the duration for which it will be maintained. If the user is not sufficiently knowledgeable or properly advised the exercise might be ineffective or, at the other extreme, dangerous or even potentially fatal.The appropriate level of exercise will also vary from one exercise session to the next because the state of health and general fitness is not constant.

One relatively recent development designed to reduce the risk of inefficiently low or dangerously high levels of exercise has been the introduction of pulse rate sensors. These usually provide a digital display of the users pulse rate. The user is advised of an upper pulse rate limit below which he may exercise safely. However, it is necessary for the user to monitor constantly his pulse rate and adjust as appropriate his level of effort and/or the mechanical load presented by the apparatus.

Some known machines include electronic calculators which calculate the upper pulse limit for a user in dependence upon the users age, weight and sex. This provides general guidance for a user, but it does not take into account the general fitness and physical characteristics of the user, or his actual physical condition at the time of each exercise session.

Thus, although the provision of a pulse rate sensor offers some degree of regulation of the level of exercise, it will be appreciated that much is dependent upon implementation by the user and the question of obtaining the optimum level of exercise has not been addressed.

According to the present invention there is provided an exercise machine comprising a member to be operated by a user, load means supplying a variable resistive force applied to resist operation of the member, a detector which monitors a physiological parameter of the user which physiological parameter alters in accordance with the degree of physical power applied to the operating member by the user, and control means which control the load means automatically in accordance with output from the detector to thereby regulate the resistive force applied to the operating member.

The user is monitored constantly and the level of exercise varied accordingly so as to ensure saftey and an optimum level of exercise.

Preferably, the control means controls the load means so as to vary the resistive force in a time dependent manner subject to output from the detector remaining with a range calculated by the control means.

Embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 is a block diagram illustrating the arrangement of an embodiment of the invention, Figure 2 is a graph illustrating the inter-relationship between variation of resistive force and pulse rate during an initial fitness test, and Figure 3 is a graph similar to that of Figure 2 but illustrating a cyclic exercise routine.

The embodiment of the invention to be described with reference to the accompanying drawings is in the form of an exercise bike.

The exercise machine includes a seat for the user to sit on and pedals to be rotated in the normal fashion of a bicycle. Hand grips are provided in front of the seat and the spacing of the seat relative to the hand grips and pedals is adjustable so as to accommodate users of different size. In a simple arrangement, the pedals may drive a fly wheel which has a braking mechanism operative against the rim thereof. In a simple embodiment the braking mechanism comprises disk pads which are forced against the rim of the fly wheel with a variable force. The force is applied via levers which are operated by a cable. The tension of the cable is adjusted by a cable drum which is rotated by an electric motor. The supply of electric current to the motor is controlled by a control unit.

The control unit receives input from a detector which monitors the physiological condition of the person exercising on the bike. In this embodiment, the physiological data which is monitored is the pulse rate of the user. The detector comprises a known sensor. The sensor is contained in a housing which is clipped to an ear lobe of the user. A light source in the housing shines light onto the users ear lobe and the reflected light is collected by a photo detector. Movement of the surface of the ear lobe in accordance with the users pulse provides electrical signals indicative of the pulse rate, in a known manner.

The various components of the exercise bike will now be described with reference to the block diagram shown in Figure 1 of the drawings. Reference U indicates a user who applies a force to the pedals of the bike in order to make them rotate. A variable resistive force is applied under the control of unit H in order to resist rotation of the pedals. The user does work in applying the force to the pedals against the action of the resistive force and thus inputs a certain physical power into the machine. The physical power is the rate at which the user does work.

Reference A donates a pulse rate detector.

Reference B donates an amplifier which has sufficient gain and frequency response to amplify and filter the signals from the detector A to the levels required for further processing.

Further processing is undertaken in the unit designated by reference C. Unit C is a signal digitising and shaping circuit which operates on the output from the amplifier unit B in accordance with subsequent processing which is to be undertaken by a digital or analogue computer. The digital or analogue computer is designated by reference D.

The computer D supplies outputs to units E, F, G and H. Unit E is a display device which indicates to the user the RPM of the pedals required at any particular instance in order to comply with the program controlled level of exercise. Unit F is a display device which indicates the instantaneous RPM of the pedals which is being achieved by the user. Unit G is a general purpose display device which selectively displays one of a number of different data items such as pulse rate, calorific equivalent of physical work expended, elapsed time or other such data items. Units I, J, K and L are optional features which will be described below.

Description will now be given of the use and operation of the exercise bike.

Use of the exercise bike is undertaken in two phases. These two phases are completed for each exercise session. The first phase comprises an initial fitness test. The user U seats himself on the bike ready to commence exercise. The detector A is clipped to one of the users ear lobes and electrical signals indicative of the users pulse rate are transmitted via the amplifier unit B and the shaper and digitiser unit C to the computer D. Receipt by the computer D of a pulse rate signal causes a visual display to be given indicating that the equipment is operational. Such visual indication may be in the form of a flashing yellow LED.

The computer D compares the monitored pulse rate with a look-up table stored in Read Only Memory. Messages are displayed on the display unit G so as to instruct the user to enter details of age, weight and sex via a keyboard. This information is relayed to the computer D where it is used to define the coordinates of the look-up table within which the permissible initial pulse rate range is located.

The computer D compares the measured pulse rate with the range values obtained from the look-up table so as to determine whether or not the users pulse rate is at a safe level for the user to undertake any exercise.

The user's pulse rate is monitored for 10 pulse beats to determine if the rate remains constant. If the user's pulse rate is within the permissible range and the rate remains constant over the 10 pulse beats, the yellow flashing light is turned off and a green light is switched on. This indicates to the user that the initial fitness test may proceed. If the user's pulse rate is outside of the permitted range or if the pulse rate does not remain constant, the computer D initiates a delay of 60 seconds and then re-tests the user's pulse rate. If the pulse rate has improved sufficiently so as to fall within the permitted range, the green light is illuminated as previously. If not, illumination of the yellow light is replaced by illumination of a red light which indicates that the user should not exercise.In these circumstances the computer D will not proceed with a program of exercise but will instead return to its quiescent state.

Once the green light has been illuminated, the initial fitness test proceeds. This stage of the initial fitness test will be described with reference to Figure 2 of the drawings. The graph of Figure 2 is a plot of user's pulse rate (shown against the left-hand vertical axis) against time. The graph also shows resistive force in terms of percentage of maximum load (indicated against the right-hand vertical axis) against time. The resistive force applied to resist rotation of the pedals is indicated by the dash line whereas the users pulse rate is indicated by the dot line. The initial decrease in pulse rate, indicated by the arrow X in Figure 2, is caused by the user relaxing from initial anxiety caused by anticipation of the exercise.

The computer D outputs a signal to the buffer and interface unit H indicating that 25% of the maximum possible mechanical load should be applied to the fly wheel. In turn, unit H ensures that the cable controlling the brake pads via the levers is subjected to a tension consistent with the required 25% load to be applied to the fly wheel. The computer D also transmits a signal to display unit E so that the required RPM is displayed to the user.

The required RPM will be set at a modest value. The user is expected to obtain the requested RPM and he is able to do this by monitoring the value indicated on display F.

There is an input from M via H to D so as to enable the instantaneous RPM of the pedals to be displayed at display F. The user is expected to maintain the requested RPM. Once the requested RPM has been obtained the computer D initiates a timing sequence so that the user continues this particular level of exercise for a set time, such as two minutes. If the required RPM is not maintained or is exceeded then the computer D sends a suitable indication to the user via display unit D and recommences the timing sequence once the required RPM is once again obtained.

During the fixed period of exercise, the user's pulse rate will increase in accordance with his physical fitness and prevailing ambient conditions, such has heat and humidity of the room in which the exercise is being conducted. Since a constant level of power is required from the user in order to complete the test, the increase in pulse rate can be considered as an accurate indication of the user's physical fitness. Throughout both phases of the exercise session, computer D monitors rate of change of pulse rate and any systolic heartbeats. The exercise will be terminated if these indicate danger to the user. For example, the detection of two systolic beats in 16 normal beats will terminate the programme. An initial pulse rate value is stored by the computer D at the start of the two minute test exercise and a final pulse rate value is recorded at the end of the two minute exercise.The ratio between the initial and final pulse rate values is calculated. Both the initial pulse rate and the calculated ratio are subsequently used by the computer to determine safe levels of exercise for the user during the immediately following exercise routine.

This subsequent exercise routine constitutes phase 2 of operation of the exercise bike.

The main exercise routine now commences and this is described with reference to Figure 3 of the drawings. Figure 3 is a graph showing the inter-relationship between resistive force applied to the pedals and the corresponding pulse rate of the user, with the same axis and dot and dash line indicators as used in the graph of Figure 2. The computer D controls a cyclic session of exercise for the user. The exercise is controlled to be within safe limits in accordance with the initial pulse rate and ratio as calculated by the computer during the initial fitness test. The detail of the cyclic form of the exercise is determined by the computer in accordance with variation of the user's pulse rate during execution of the exercise itself. In particular, the computer calculates the pulse rate recovery time (R1, R2, R3) for relatively short periods of exercise (El, E2, E3).The recovery period between short periods of exercise, the resistive load applied to control the user's power input and the duration of the relatively short periods of exercise are all determined by the computer in accordance with the instantaneous pulse rate of the user as the exercise progresses. Thus, the user is required to work under a certain percentage load and the increase in pulse rate is monitored. The power input required from the user is indicated to the user by way of the RPM indicators E and F, as described above.

The computer calculates an initial upper pulse rate limit (P1) from the results of the initial test. When the user's pulse rate equals the initial upper pulse rate limit (P1), the percentage load is reduced to a very low value.

As a consequence, the user will have to do very little work in order to maintain the required RPM and his pulse rate will decrease.

The computer monitors the decrease in pulse rate. When the user's pulse rate reaches a level (PO) predetermined by the computer, for example initial pulse rate (from the initial fitness test) plus 20%, the computer sends a signal to unit H so as to cause the percentage load to be increased. This increase is to a value (L2) above the previous highest level (L1). The time (R1) taken for the pulse rate to decrease from the initial upper limit (P1) to the predetermined lower limit (PO) is calculated.

This provides the pulse recovery time (R1) and this information is used to set the level (L2) to which the new percentage loading is increased and the level (P2) to which the upper pulse rate limit is increased. The above described procedure is then repeated. As the exercise proceeds, it can be expected that the relatively short periods of exercise (El, E2, E3, E4) will decrease in duration, the recovery intervals (R1, R2, R3) will increase in duration and the percentage of the maximum possible loading (L1, L2, L3, L4) applied to resist rotation of the pedals will also increase.

The exercise continues until; (a) an overall pre-set period of time elapses, (b) the user elects to stop, (c) a pre-set increase in recovery time is reached or (d) an emergency stop condition occurs. An emergency stop condition may occur if the pulse rate of the user moves outside of the safe range as calculated by the computer.

Description will now be given of an arrangement in which the optional features designated by reference numerals I, J, K, and L will be described. Unit I designates an auxiliary computer which works in conjunction with but under control of computer D. The auxiliary computer I controls subsystems designated by reference numerals J, K and L. Unit J is a speech synthesizer. Unit K is a printer and unit L is a magnetic card read/write device. These optional features may be used to implement some or all of the system described below.

The printer J is arranged such that at the end of the exercise session, the exercise machine provides a printed record of the user's performance. This information will include date and time. It will also include information concerning the resistive force applied during various stages of the exercise together with details of the corresponding pulse rate performance. This information might be assimilated by computer I so as to print an overall figure of merit in accordance with all of the factors monitored during the exercise session.

In a further enhancement, each user is provided with a credit card type of magnetic information carrier. The magnetic information in cludes the user's name, address, age, weight, sex, previous exercise data and the like. The magnetic card is inserted into unit L prior to commencement of the initial test. This obviates the need for the user to enter the basic details such as age, weight and sex. The system can be extended so that the magnetic card read/write unit L reads details such as date and performance of last exercise session from the magnetic card so that this information can be used by computer D in setting the level of exercise for the current session. At the end of the current session the unit L writes details of the current session back onto the magnetic card so that these can be used for subsequent exercise session.

The speech synthesisor K receives information from unit L via computer I so as to issue an audio welcome to the user including speaking the users name and date and performance of the last exercise session. Unit K presents in audio form a summary of the users performance at the end of the exercise session, and bids the user farewell. During the exercise session, unit K is used to issue audio encouragement to user and to advise of the approach of pulse limits, etc.

One embodiment of the invention has been described above. It will be readily understood by those skilled in the art that many variations of the detail of the above described embodiment can be made without departing from the scope of the present invention. Some of these variations will be discussed below.

The exercise machine has been described as an exercise bike. Other forms of exercise machine may be employed and examples are a bench press and a running platform.

Many variations are possible for the detailed manner in which a resistive force is applied against the effort expended by the user.

Examples include the automatic addition of mass to a weight moved by the user, mechanical slipping clutch arrangements and electrical and electro-mechanical devices.

In the described and illustrated embodiment, the physiological parameter of the user which is monitored by the detector A is the user's pulse rate. Any suitable physiological parameter may be used in addition to or in the place of the user's pulse rate. The requirement is that the physiological parameter should vary sufficiently within the region of safe exercise to be undertaken so as to be susceptible of accurate monitoring while the exercise is in progress. Examples of suitable physiological parameters may include pulse rate, temperature, blood pressure, muscle potentials (myography) and PGR (psycho galvanic reflex).

In the above described embodiment reference is made to the use of a reflective mode opto-electronic sensor for measuring pulse rate. Suitable pulse rate sensors may also be based upon other types of sensors such as: transmissive opto-electronic, electrocardiographic, capacitive, plethysmographic, reographyic, echocradiographic (ultra sonic), audiocardiographic (sonic), blaistocardiographic and other such sensors.

Suitable temperature sensors make consist of thermopiles, thermocouples, thermistors, semi-conductor junctions, infra-red radiation devices, devices using the expansion of liquids and/or gases, devices using the deformation of solids or other such devices.

Blood pressure sensors may include inflatable cuffs, intravenous methods, photoelectric systems, reographic systems, plethysmorgraphic systems and other such methods and systems.

Suitable muscle potential (myography) sensors may comprise: surface (skin) electrodes, insertion electrodes, inplanted electrodes, capacitive electrodes and other similar devices.

Suitable psycho galvanic reflex sensors may include constant current systems, constant voltage systems and systems using both direct and alternating currents and voltages.

The display unit G may consist of a CRT, or of an LED or LCD in the form of numeric, alpha-numeric or dot matrix displays. Other alternatives include back light or projected displays, bar graphs or analogue meters.

The information to be displayed on unit G may include data relating to the user and data relating to the exercise machine. Data relating to the user might include: pulse rate, respiration rate, blood pressure, heart recovery rate, calorific equivalent, temperature, muscle activity, initial fitness test score. Data relating to the exercise machine may include: RPM, speed, reluctance/load, elapsed time, elasped exercise curve, cyclic exercise-current cycle/current position, or other such information.

Claims (20)

1. An exercise machine comprising a member to be operated by a user, load means supplying a variable resistive force applied to resist operation of the member, a detector which monitors a physiological parameter of the user which physiological parameter alters in accordance with the degree of physical power applied to the operating member by the user, and control means which control the load means automatically in accordance with output from the detector to thereby regulate the resistive force applied to the operating member.

2. An exercise machine as claimed in claim 1, wherein the control means controls the load means so as to vary the resistive force in a time dependent manner subject to output from the detector remaining within a range determined by the control means.

3. An exercise machine as claimed in claim 1 or 2, further comprising data input means by which a user can supply the control means with personal data concerning personal charac teristics.

4. An exercise machine as claimed in any preceding claim, further comprising memory means for storing information in a look-up table form.

5. An exercise machine as claimed in claim 4, wherein the control means in order to conduct a pre-exercise test are arranged; to read information out of the memory means in accordance with said personal information, to compare the read-out information with output from the detector, and as a result of the comparison to indicate to the user whether or not the user should proceed to exercise.

6. An exercise machine as claimed in any preceding claim, wherein the control means monitors the output of the detector so as to determine a maximum value of the said parameter above which exercising should not proceed, the control means being arranged to control the load means so as to remove the resistive force applied to the operating member if the said maximum value is exceeded.

7. An exercise machine as claimed in any preceding claim, wherein the control means in order to conduct an initial fitness test are arranged; to indicate to the user a required level of physical power to be applied to the operating member; to indicate to the user a period of time for which said level of power is to be applied; and to monitor the output of the detector during said period of time to detect changes in said parameter which indicate that the user should not exercise.

8. An exercise machine as claimed in any preceding claim, wherein the control means in order to control an exercise routine are arranged; to determine a first resistive force and a first required level of physical power both to be applied to the operating member; to indicate to the user the said first required level; to indicate to the user a first exercise time during which time the first required level of power is to be applied; to undertake a first monitoring of the output of the detector dur ing or at the end of a first recovery time, which recovery time is subsequent to the first exersise time; to determine from the said first monitoring a second resistive force and a second required level of physical power both to be applied to the operating member; and to indicate to the user the said second required level of physical power.

9. An exercise machine as claimed in claim 8, wherein the control means are arranged to repeat for a plurality of times the sequence of; monitoring during or at the end of a recovery time, determining a new resistive load and new required level of physical power to be applied to the operating member, and indicat ing the new required level of physical power to the user.

10. An exercise machine as claimed in any preceding claim, further comprising display means for displaying variable information to the user, said variable information including the instantaneous physical power applied to the operating member and the said indications from the control means.

11. An exercise machine as claimed in any preceding claim, wherein the control means monitors the output from the detector during the whole of the period for which the exercise machine is in operation to detect changes in said parameter to indicate that the user should not continue to exercise, the control means being arranged to control the load means so as to remove the resistive load if any such changes in the said parameter are detected.

12. An exercise machine as claimed in claim 2, wherein said data input means comprises a keyboard.

13. An exercise machine as claimed in claim 2, wherein said data input means comprises a card reading device capable of reading a card carrying the said personal data.

14. An exercise machine as claimed in claim 13, wherein the card reading device writes data to the said card under the control of the control means when the control of an exercise session is complete.

15. An exercise machine as claimed in any preceding claim, further comprising a voice synthesiser for providing information to the user.

16. An exercise machine as claimed in any preceding claim, further comprising a printer controlled by the control means for providing a printed summary of the exercise undertaken by the user.

17. An exercise machine as claimed in any preceding claim, wherein the exercise machine is in the form of an exercise bike.

18. An exercise machine as claimed in claim 17, wherein the required level of physical power to be applied to the operating member is identified in RPM of the pedals of the bike.

19. An exercise machine as claimed in any preceding claim, wherein the physiological parameter is pulse rate.

20. An exercise machine substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.