FR3020675A1 - METHOD OF CALCULATING A CHARACTERISTIC VALUE OF A COURSE THAT CAN BE ACHIEVED DURING PHYSICAL ACTIVITY - Google Patents

Abstract

The invention relates to a method for calculating a characteristic value of a course that can be accomplished during a physical activity, the course being described by descriptive parameters. The method comprises steps of receiving a series of location data representative of the path; dividing the course into segments and processing the location data series to determine the segment descriptive parameters; and determining the characteristic value of the course from the descriptive parameters of the segments and from a model specific to physical activity. The invention also relates to a method for selecting courses that can be completed during a physical activity, in a database associating courses and the characteristic values of these courses.

Description

FIELD OF THE INVENTION The present invention relates to a method for calculating a characteristic value of a path likely to be traversed during a physical activity of the invention. accomplished during a physical activity. It also relates to a method for selecting such a path within a database in which paths and path characteristic values are associated. BACKGROUND OF THE INVENTION People practicing physical activity, such as running, road biking, cross-country skiing or mountain biking are often looking for a new path for practice their activity. It is then common for the practitioner to consult magazines, topo-guides OR dedicated websites allowing him to discover and choose for himself, for a future practice, courses that he has never realized before. The problem encountered in this situation is that it is difficult for the practitioner to determine for sure that the courses presented correspond to his practice. And in certain circumstances (for mountain courses in particular) this uncertainty can lead to situations of endangerment.

The document W02013070572 attempts to overcome this problem by proposing a method of recommending courses for a physical activity, the recommended course being adapted to the user.

To do this, the method collects location data as well as personal data relating to the physical exertion provided by the practitioner (such as his or her heart rate, instantaneous speed) upon completion of the physical activity. These data make it possible to establish determined characteristic course segment sizes specific to a particular practitioner. A network of neurons trained from these data then makes it possible to offer 10 relevant recommendations of course, adapted to this determined practitioner. However, such a method is not entirely satisfactory because it requires the collection of personal data on the practitioner (especially related to the effort); and therefore requires to equip it with data recording devices that are not always available or that can be expensive (heart rate monitor for example). It is also well known that the training of a neural network requires a large amount of collected data. As a result, the number of routes and personal data to be provided by a user before the network can deliver relevant proposals may be excessive; and divert the user from the use of such a service. OBJECT OF THE INVENTION An object of the invention is to propose a method making it possible to suggest courses similar to a standard course provided or designated by a user and obviating the aforementioned drawbacks.

Another object of the invention is to propose a method of calculating a characteristic value of course which is not based on the efforts provided by a practitioner during the realization of this course. And the calculation of this characteristic value is readily available. BRIEF DESCRIPTION OF THE INVENTION In view of the achievement of the above-mentioned objects, the object of the invention proposes a method of calculating a characteristic value of a course of action that can be accomplished during a physical activity, the path being described by descriptive parameters, the method comprising the following steps: receiving a series of location data representative of the path; division of the segment path and processing of the location data series to determine the descriptive parameters of the segments; determination of the characteristic value of the journey from the descriptive parameters of the segments and from a model specific to the physical activity. The characteristic value determines, at the end of this method of calculation, the degree with which the completion of a course will appeal to certain capacities of the practitioner. It can be for example its endurance, its strength or its technical mastery.

According to an essential aspect of the invention, the calculation of the characteristic value implements a model specific to physical activity.

The characteristic value of a course can therefore be established on the basis of information characterizing the course and without resorting to information of efforts provided by the practitioner during the realization of this course.

In a particular embodiment of the invention, the physical activity-specific model transforms the segment descriptive parameters into an equivalent descriptive parameter in a reference topographic environment. The equivalent descriptive parameters can then be combined to establish the course characteristic value. In a preferred embodiment of the invention, the model specific to physical activity is derived from a specific relationship linking at least certain descriptive parameters to speed. In a particular embodiment of the invention, the specific relation comprises a set of parameters, these parameters being able to be determined by an identification method. There is thus a predetermined specific relationship to physical activity which makes it possible to easily establish the characteristic value of the course without passing through the method of calculation by a particular learning phase to a practitioner. The invention also relates to a method for selecting courses that can be accomplished during a physical activity, in a database associating courses and the characteristic values of these courses, the method comprising the following steps of: determination of the typical characteristic value of a typical route; - Selection of the routes, in the database, whose characteristic values fill, with the characteristic characteristic value, a predetermined criterion.

The invention finally relates to a computer program comprising instructions for executing the steps comprising the calculation method and the selection method that is the subject of the invention.

According to other advantageous and nonlimiting features of the invention, taken alone or in combination: the location data include longitude, latitude. the processing step comprises a calculation of certain descriptive parameters of the segments from the series of location data. the processing step comprises establishing a request, from the location data series, from a remote information source. - the descriptive parameters are chosen from the list formed of the slope, the length, the nature of the track. - The nature of the path of at least a part of the segments is determined by request from a geographic information source. the nature of the path of at least a portion of the segments is determined according to the nature of the adjacent segments. the descriptive parameters include the slope, the length and the nature of the path, and the equivalent descriptive parameter corresponds to an equivalent length for a slope of a determined value and a determined path nature. the slope of determined value has a value of zero, and the determined lane nature is the road. the descriptive parameters comprise the slope and the nature of the track, and the equivalent descriptive parameter corresponds to an equivalent climb slope for a determined track nature. the descriptive parameters include the slope and the nature of the track, and the equivalent descriptive parameter corresponds to an equivalent descent slope for a determined lane nature.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood in the light of the following description of the particular non-limiting embodiments of the invention with reference to the attached figures, in which: FIG. 1 represents the specific relations linking the slope of a course at the speed of completion of this course for mountain biking and running; FIG. 2 and FIG. 3 represent general views of the calculation and selection methods that are the subject of the invention. DETAILED DESCRIPTION OF THE INVENTION In general, the invention associates with a course a characteristic value of this course. This association subsequently makes it possible to suggest to a user, for a given activity, courses similar to a standard course designated or provided by him. The implementation of the method which is the subject of the invention requires the configuration of a set of parameters making it possible to establish this characteristic value, presented in the following paragraphs.

Characteristic value of a course The physical activities, by their very nature, can ask a practitioner according to different aspects: some physical activities can thus request technical abilities (skiing) or endurance abilities (marathon).

Other physical activities will require the practitioner on a multiplicity of abilities, for example in endurance, power and technique (VTT). In general, the characteristic value of a course is a magnitude, descriptive of the topography of the course (a slope, a length, for example), which represents the degree with which the course solicits a capacity of the practitioner during the course. a given physical activity. A path may be associated with a single or a multiplicity of characteristic values. Descriptive parameters The descriptive parameters identify the topographic characteristics of the route (length, slope, for example) which contribute to establish its characteristic value. By way of example, to represent the endurance demand of a course, it is useful to have information on the length of the course. The topographic feature of length therefore forms a descriptive parameter in this case.

There is a great deal of latitude in the choice of the characteristic value and the descriptive parameters characterizing at best a physical activity. This choice is guided by the knowledge and experience of this physical activity, for example by looking for the topographical information that determines the effort to be provided or the pleasure experienced by a practitioner during the completion of a course. Segment of course A segment of a route is called a segment and has homogeneous topographical features over its length. For example, it may be a portion of the course on which the slope is relatively constant, and the nature of the communication path (road, trail, etc.) unchanged. A route segment is characterized by descriptive segment parameters, such as {segment length, segment slope, track nature}. Model specific to physical activity In a very general way, the model specific to physical activity is the relationship that makes it possible to determine the characteristic value of a course from the descriptive parameters of segments. This relationship can take many forms: it can be a numerical function defining the characteristic value from the descriptive parameters. It can be a relationship established in the form of a value table, or a set of fuzzy logic rules. In a preferred embodiment of the invention, the physical activity-specific model transforms the descriptive parameters of a segment into an equivalent descriptive parameter in a reference topographic environment.

This transformation applies for all or part of the segments making up the course. The characteristic value of the path is then established by combining equivalent descriptive parameters, such as, for example, a sum, an average, a maximum or minimum value. By way of example, a segment defined by descriptive parameters of {length, slope, nature of the path} is transformed into an equivalent descriptive parameter defined by a length in a reference topographic environment defined by a road of zero slope. And the characteristic value of course can be established as the sum of the equivalent descriptive parameters of each segment (or of a number of them). In a preferred embodiment of the invention, the physical activity-specific model which operates in a manner of normalizing a segment in the reference topographic environment is derived from a specific relationship to the physical activity. 20 Specific relationship Physical activities each have their particular characteristics. FIG. 1 compares, by way of example, for the physical activities of MTB (curve A) and running (curve B), the specific relationship linking the slope of a course or segment of course to the speed of realization of this course or segment of course. It is observed that the two curves each have marked differences, especially in terms of maximum speed. This specific relationship to physical activity is not directly related to a practitioner's performance. Rather, it is a universal relationship that aims to characterize physical activity as such.

For a broad class of physical activities, the specific relationship links at least some descriptive parameters to the speed of completion of a course. For this broad class of physical activities, and as shown in Figure 1, the speed decreases monotonically with the increase of the slope, when it is positive; and the speed increases with the increase of the slope (in absolute value) when this one is negative, until a value of threshold slope, beyond which the speed decreases, for obvious reasons of safety. By way of example, the velocity v carried out on a path of slope p can very generally be expressed by an equation of the following form: v (p) = v0 / (1 + alpha * p) ^ beta for p> 0 v (p) = v0 * Exp (- p * (p-delta) / sigma) for p <0 Where vO, alpha, beta, delta, sigma are parameters of the relation. The parameters of this relationship can be set to give an empirically selected profile for a given activity.

Preferably, however, these parameters are determined by a parametric identification method. In a manner well known per se, this method makes it possible to determine the parameters of a given relationship, from a limited number of measurements collected (in this case of slope and speed) using a device. recording (GPS for example) and with a diverse population of practitioners.

Whatever the method of determining the parameters of the relation, the equation provided with its parameters characterizes a sporting activity. And the given specific relation thus makes it possible to define the physical activity-specific model that transforms a segment defined by its descriptive parameters of segment {length d, slope p} into an equivalent descriptive parameter of length d 0 in a reference topographic environment. of zero slope, noting that 10 dO = d * (1 + alpha * p) ^ beta for p> 0 dO = d / Exp (- p * (p-delta) / sigma) for p <0 Example of implementation work in the case of mountain biking. ATV is a physical activity that solicits the endurance, power and technical skills of the practitioner. A first characteristic value (endurance) of path length is defined as the sum, for positive slope segments, of equivalent descriptive parameters of length. It is actually considered in this example that MTB, a segment of course with a negative slope contributes to this characteristic value. A second average climb slope characteristic (power) value is defined as the average, for segments with a positive slope, equivalent slope descriptive parameters. A third characteristic value (technique) of average downhill slope of a course is defined as the average, for the segments having a negative slope, of the equivalent slope descriptive parameters.

In addition, mountain biking is strongly impacted by the nature of the road used: depending on whether it is a road, a path or a path, the behavior of the practitioner will be directly affected.

Consequently, the descriptive parameters useful for the determination of the characteristic quantities are determined as being the length, the slope, and the nature of the path. To characterize this physical activity, a series of preparatory measures was collected from practicing various levels, these measurements including data of speeds and slopes for the different nature of ways (road, path, path). For each of the lane nature, a specific velocity-slope relationship is identified by a known parametric identification method based on the following models: / r (p) = v0 r / (1 + alpha r * p) ^ beta r for p> 0 / r (p) = v0 r * Exp (- p * (p-delta r) / sigma r) for p <0 Where v0 r, alpha r, beta r, delta r , sigma r are the parameters of the relationship when the lane is a road. / c (p) = v0 c / (1 + alpha c * p) ^ beta c for p> 0 / c (p) = v0 c * Exp (- p * (p-delta c) / sigma c) for p <0 25 Where v0 c, alpha c, beta c, delta c, sigma c are the parameters of the relation when the path is a path. / s (p) = v0 s / (1 + alpha s * p) ^ beta s for p> 0 30 V s (p) = v0 s * Exp (- p * (p-delta s) / sigma s) for p <0 Where v0 s, alpha s, beta s, delta s, sigma s are the parameters of the relationship when the path is a path.

Concerning the endurance characteristic value, it is considered that the reference topographic environment is a zero slope on the road. In other words, the physical activity-specific model transforms the descriptive segment parameters (length, slope, track nature) into equivalent length on a zero-slope road. Recall that the segments with a negative slope are not taken into account in the computation of this characteristic value. We denote d 0, d 0 c, d 0 s the distances respectively in zero slope on road, path and path and we note dp r , dp c, dp s the distances respectively in slope p on road, road and path. From the previous relations, we can establish the model specific to physical activity as: d = dp r * (1 + alpha r * p) ^ beta r if the path is a road and the slope is positive; Assuming that d0 r = (v0 r / v0 c) * d0 c, we get: 25 dO r = (v0 r / v0 c) * dp c * (1 + alpha c * p) ^ beta c if the path is a path and the positive slope; Similarly, assuming that d0 r = (v0 r / v0 s) * d0 s, we get: dO r = (v0 r / v0 s) * dp s * (1 + alpha s * p) ^ beta s if the path is a path and the positive slope. The characteristic endurance value will be determined as the sum, for each segment having a positive slope, of the distance d 0 r determined from the preceding equations, and according to the nature of the path. Concerning the characteristic power value, it is considered that the reference topographic environment is the road. In other words, the physical activity model transforms the descriptive segment parameters into an equivalent slope on the road. For a road segment, this equivalent slope is directly available. It is postulated that two slopes up on different lane types are equivalent if they run at the same speed. For example one can write for a slope pr> 0 on a road and a slope pc> 0 on a path that 20 vr (pr) = vc (pc), ie v0 r / (1 + alpha r * pr) ^ beta r = v c0 / (1 + alpha c * pc) ^ beta c Let, in the end: pr = 1 / alpha r [(v0 r / vp c) ^ 1 / beta r - 1] 25 With vp c = v0 c / (1 + alpha c * pc) ^ beta c A very similar equation makes it possible to express the slope as an equivalent climb from a slope when mounted on a path.

The characteristic power value shall be determined as the mean, for each segment with a positive slope, of the slope p r determined from the preceding equations, and according to the nature of the channel.

Concerning the technical characteristic value, it is considered that the reference topographical environment is the road. In other words, the physical activity model transforms segment descriptive parameters that have a negative slope into an equivalent slope on the road. The approach used is precisely the same as in the previous calculation, based this time on the specific relationship between the speed and the slope when the latter is negative. The characteristic value of the technique will be determined as the average, for each segment with a negative slope, of the slope p r determined according to the established equations.

The example given in the case of ATV can be easily adapted to other physical activities. Thus, in the case of walking and all associated activities ("Trail", marathon, etc.) where the completion of a course or a portion of downhill course requires physical effort, the characteristic value of endurance will also take into account the equivalent lengths of segments with a negative slope. To do this, we will rely on the specific relationship linking the speed to the slope, when the latter is negative.

For sliding sports, or cycling, we can use characteristic values similar to those presented in the case of mountain biking, including not taking into account in the calculation of the characteristic value of endurance segments with a negative slope, insofar as these do not contribute little or nothing to the overall effort of achieving a course. To summarize this preliminary part of the description, the invention makes it possible to dispense with a practitioner's personal data and in particular the efforts he makes to suggest relevant courses, by implementing a specific relationship to a physical activity, and describing its universal characteristics. This specific relationship operates as a sort of normalization of segment descriptive parameters in a topographic reference environment, to determine equivalent descriptive parameters. The characteristic value of the course is determined by combining the characteristic parameters of course.

These elements being set, the detailed description of the method according to the invention is made with reference to Figure 2 and Figure 3, given by way of non-limiting examples.

A user wishes to receive course suggestions for a specific physical activity based on a typical course. In the case where the typical route does not exist in a route database, the user must provide this route in order to determine its characteristic value. In a variant of use, the user wishes to provide a new path so that it can be suggested later to other users. In this case also, the characteristic value of this course is determined. Determining a characteristic value of a route For this purpose and during a first step S1, a series of location data DL1; DL2; DL3 representative of a path P is transmitted by the user and received on a server S, or any other form of system having reception / transmission, storage and calculation capabilities.

This series of DL1 location data; DL2; DL3 is transmitted by the user via a communication network to the server, for example via a 3G or 4G cellular network, or an Internet network. The location data series may consist of GPS data, or more generally longitude and latitude data of a particular geographic point. The data may optionally include altitude data from that particular point.

Acquisition of DL1 location data series; DL2 can be obtained by recording, during the completion of the course by a practitioner, for example using a GPS watch 2 of a mobile phone 1 provided with a location function.

The acquisition can also be obtained by any other means, for example the series of location data DL3 can be created manually by the user by interactively drawing the path P on a map presented on the screen of a computer. a second step S2, the path P is divided into segments and the series of location data DL1; DL2; DL3 processed to determine the descriptive parameters Sgi of these segments. This second step comprises a sub-step S21 for preprocessing the location data DL1; DL2; DL3 so as to allow the constitution of a coherent set of path segments.

Indeed, the series of location data DL1; DL2; DL3 may include an excessive or insufficient number of data. This situation may have its origin, for example, in the method of data acquisition, a manual acquisition that may lead to the definition of a route too approximate, which should be completed by introduction of complementary geographical positions. This situation can also come from the temporary loss of the GPS signal, or even after pauses of recovery during the completion of the course which lead to duplicate the registration of the same geographical position. The determination of the appropriate number of segments or the appropriate length of each segment is related to the nature of the physical activity. In general, we will try to define the segments as portions of the course having on their length homogeneous topographic characteristics.

The method continues with a sub-step S22 for determining the descriptive parameters of the segments Sgi. This substep of determination can be performed in multiple forms. Some values of these parameters can be entered directly from the location data DL1; DL2; DL3 preprocessed in step S21 or by direct calculation from these data.

This is the case for example when the segment descriptive parameters include the location information of the geographical point of origin or the end of the segment, length of the segment, etc.

Other segment descriptive parameter values may be obtained in response to a request sent to a database BD1, which may be remote from the server S. Thus, the calculation of the slope of a segment requires, if the information of altitude is not provided in the location data, to search the altitude information of the geographical points of origin and end of this segment. This can be achieved by addressing one or more appropriate requests to a geographic database, each request returning for example the altitude of the geographical point provided as a parameter. Similarly, the nature of the communication path taken by the route (for example a road, a path, a path) can be obtained from a geographic information database, such as the "openstreetmap" database. Other information, including meteorological information can be obtained in a similar manner, for example to determine a descriptive parameter of the state of the track (dry, wet, muddy, etc.).

The parameters of the segments Sgi may optionally be the subject of additional processing, in a substep S23, to possibly correct or smooth approximations of acquisition of the location data DL1; DL2; DL3.

It may also be necessary to determine certain parameters of a segment according to the value of the parameters of the adjacent segments. Thus, if the nature of the lane for all segments has been determined as a road, except for a segment for which the type of lane of communication has been determined as a lane, it will be possible to choose to make a correction by affecting the lane. type "road" to this isolated segment. It may also be to omit certain segments for further processing, for example the end segments of course, because it is possible that they are not representative of the course itself. It may still be to omit one or more segments that obviously can not match the reality of the course. This would be the case if a segment had a height difference of several thousand meters. It may finally be to add additional segments to the path P, these additional segments to join from a determined starting point that can be set by the user, the initial geographical point of the course P.

At the end of this step S2, there is a set of descriptive parameters of the segments Sgi describing a path P. In a following step S3, at least one characteristic value VC of the path P is determined from the descriptive parameters of the parameters. Sgi segments and from the model M specific to the chosen physical activity. According to the invention, this determination of the characteristic value VC of the course P is not based on the efforts provided by a practitioner during the realization of this course. In a particular mode of implementation, the model M 30 of the physical activity transforms respectively the characteristic parameters Sgi of the segments into equivalent characteristic parameters in a reference topographic environment. The characteristic value VC of the path P is then obtained by combining the equivalent characteristic parameters of the segments. The combination can be a sum, a weighted sum (for example to assign more weight to end-of-course segments than to the beginning segment), an average, a maximum, a minimum ... At the end of this step S3, a characteristic value VC of the path P is available which can be stored in a database BD2 in association with the path P (as represented by the branch a in FIG. 3) and / or used as a point input of the selection method according to the invention and whose description follows in the following paragraphs (as represented by branch b in Figure 3).

Suggestion of a course The method according to the invention allows a user to obtain a selection of courses P1, P2, P3 likely to be accomplished during a specific physical activity, the selection taking place within the BD2 database associating paths Pi and VCi path characteristic values. The paths Pi can be represented in the database by the series of location data, or by a label pointing to this series. Other data can be associated with a route in the database: description of the course, photos, user comments, etc ...

In a next step, the selection method comprises determining the characteristic value VCT of a typical path PT.

According to a first embodiment, the typical path is provided by the user in the form of a series of location data DL1; DL2; DL3. And the characteristic value VCT type is obtained via the calculation method described above. According to a second embodiment, the PT type path is designated by the user from the prerecorded paths in the database DB2, and the characteristic value VCT associated with the designated path type PT is obtained directly from the database . The designated path may correspond to a route that the user has already completed and recorded in the DB2 database or a route presented for example on the screen of the computer 3.

Whatever the embodiment chosen, at the end of this step a characteristic value VCT is available. In a next step S4, the paths P1 are selected; P2; P3 in the database BD2, the characteristic values of which fulfill, with the characteristic characteristic value, a determined criterion. According to a first embodiment, this step may correspond to selecting in database BD2 a chosen number, 5, 10 or 20 for example, of path P1; P2; P3 having characteristic values closest to the characteristic value VCT.

According to a second embodiment, this step may correspond to selecting in the database BD2 the paths P1; P2; P3 having a difference with the typical characteristic value below a given threshold, for example a difference smaller than 10% of the characteristic value VCT. The selected course (s) Pl; P2; P3 at the end of this step, can then be delivered to the user, for example by presenting them in the form of a list or map on the screen of the computer 3, the telephone 1, or by loading data. locations (which may be associated with the course in the database) in a GPS watch 10 or a mobile phone. Additional criteria to the characteristic course value may be used to assist in the selection of relevant courses for the user. Thus, by specifying in his query a geographical region of interest, the user may restrict the selection to a geographical region of residence or in which he plans to move. Other types of personal preferences to the user may also be included in this selection step S4, in order to provide the user with the most relevant course suggestions. For example, it may be for the user to indicate that he wishes to obtain suggestions for courses having a level of difficulty higher or lower than the courses he submits or designates. Naturally, the invention is not limited to the embodiments described and alternative embodiments can be made without departing from the scope of the invention as defined by the claims. In particular, the user can designate several PT type paths, in which case the characteristic value VCT to be retained can be formed by a combination (an average of

Claims (21)

CLAIMS1 A method for calculating a characteristic value (VC) of a path (P) that can be accomplished during a physical activity, the path being described by descriptive parameters, the method comprising the following steps: - reception a series of location data (DL1, DL2, DL3) representative of the route; dividing the path into segments and processing the location data series to determine the segment descriptive parameters (Sgi); determination of the characteristic value (VC) of the path (P) from the descriptive parameters of the segments (Sgi) and from a model (M) specific to the physical activity. 2 calculation method according to claim 1 wherein the model (M) specific to the physical activity transforms the descriptive parameters (Sgi) of a segment into an equivalent descriptive parameter in a reference topographic environment. 3. Calculation method according to the preceding claim, wherein the step of determining the characteristic value (VC) of the path P comprises a sum of equivalent descriptive parameters. 4. Computing method according to claim 2, wherein the step of determining the characteristic value (VC) of the path (P) comprises an average of equivalent descriptive parameters. 5. Calculation method according to one of the preceding claims wherein the model (M) specific to the physical activity is derived from a specific relationship linking at least some of the descriptive parameters to speed. 6. Calculation method according to the preceding claim wherein the specific relationship also implements a set of parameters. 7. Calculation method according to the preceding claim wherein the set of parameters is determined by an identification method. 8. Calculation method according to one of the preceding claims wherein each location data comprises the longitude, the latitude. 9. Calculation method according to one of the preceding claims wherein the processing step comprises a calculation of certain descriptive parameters of the segments (Sgi) from the series of location data (DL1, DL2, DL3). 10. Computation method according to one of the preceding claims wherein the processing step comprises the establishment of a request, from the series of location data (DL1; DL2; DL3), from a source remote information. 11. Calculation method according to one of the preceding claims wherein the descriptive parameters arechoisis in the list formed by the slope, the length, the nature of the way. 12. Calculation method according to one of the preceding claims, in which the descriptive parameters comprise the nature of the channel and, during the processing step, the nature of the channel of at least a portion of the segments is determined. by request from a geographic information source. 10 13. Calculation method according to the preceding claim wherein, during the processing step, the nature of the path of at least a portion of the segments is also determined according to the nature of the adjacent segments. 15 14. Computing method according to one of Claims 2 to 13, in which the descriptive parameters comprise the slope, the length and the nature of the track, and the equivalent descriptive parameter corresponds to an equivalent length for a slope of a given value. and a determined path nature. 15. Calculation method according to the preceding claim, wherein the determined slope has a zero value, and the nature of the determined path is the road. 16. The calculation method according to one of claims 2 to 13, wherein the descriptive parameters comprise the slope and the nature of the lane, and the equivalent descriptive parameter corresponds to an equivalent uphill slope for a given lane nature. 17. Calculation method according to one of claims 2 to 13, wherein the descriptive parameters include the slopeand the nature of the path, and the equivalent descriptive parameter corresponds to a slope equivalent descent for a determined path nature. 18. A method for selecting courses that can be completed during a physical activity, in a database (BD2) associating courses (Pi) and the characteristic values of these courses (VCi), the method comprising the steps following: - determination of a typical characteristic value (VCT) of a typical path PT according to the calculation method according to any one of the preceding claims; selection of the paths (P1, P2, P3) in the database (BD2) whose characteristic values fulfill, with the characteristic value VCT, a predetermined criterion. 19. Selection method according to claim 18, the predetermined criterion of selecting the paths (P1; P2; P3) whose characteristic values have a difference with the characteristic characteristic value (VCT) below a predetermined threshold. The selection method according to claim 18, the predetermined criterion of selecting a selected number of paths (P1; P2; P3) having characteristic values closest to the standard characteristic value (VCT). A computer program comprising instructions for executing the steps of the method according to any one of the preceding claims, when said program is executed by a computer.