ISO/DIS 20957-5:2025(en)

ISO/TC 83

Secretariat: DIN

Date: 2025-11-06

Stationary training equipment — Part 5: Stationary exercise bicycles and upper body crank training equipment, additional specific safety requirements and test methods

Équipement d’entraînement fixe — Partie 5: Bicyclettes d’entraînement et équipement d’entraînement manivelle d'haut de corps, exigences spécifiques de sécurité et méthodes d’essai supplémentaires

© ISO 2025

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Contents

Foreword v

Introduction vi

1 Scope 1

2 Normative references 1

3 Terms and definitions 1

4 Classification 2

5 Safety requirements 5

5.1 General 5

5.2 Transmission elements and rotating parts 5

5.3 Temperature rise 6

5.4 Loading 6

5.4.1 Seat pillar and frame 6

5.4.2 Handlebar and frame 6

5.4.3 Pedal and frame 6

5.5 Seat pillar — Seat 6

5.5.1 Insertion depth 6

5.5.2 Seat adjustment 6

5.5.3 Seat tilting 7

5.6 Handlebar stem 7

5.7 Stability 7

5.8 Additional requirements for recumbent stationary exercise bicycles, upper body crank training equipment and combined crank training equipment 7

5.8.1 Combined crank training equipment 7

5.8.2 Seat system 7

5.9 Additional classified requirements 7

5.10 Endurance 11

5.11 Additional instructions for use 11

5.12 Additional warnings 11

6 Test methods 11

6.1 General 11

6.1.1 Dimensional check 11

6.1.2 Visual examination 11

6.1.3 Tactile examination 11

6.1.4 Performance test 11

6.2 Testing of temperature rise 12

6.3 Testing of transmission elements, rotating parts, squeeze and shear points 12

6.3.1 Crank and stationary parts of the construction 12

6.3.2 Other moving parts 12

6.4 Testing of loading 12

6.4.1 Seat pillar and frame 12

6.4.2 Handlebar and frame 12

6.4.3 Pedal and frame 13

6.5 Testing of seat tilting 13

6.6 Testing of seat back rest 13

6.7 Testing of stability 13

6.8 Description of the test device 13

6.9 Testing of constant power mode 14

6.10 Testing of heart rate control mode 14

6.11 Testing of power accuracy for class A and class B 14

6.11.1 General 14

6.11.2 Crank training equipment with speed independent resistance system 14

6.11.3 Crank training equipment with speed dependent resistance system 15

6.12 Testing of power repeatability for class B 16

6.13 Endurance test 16

6.13.1 Crank training equipment with speed independent resistance system 16

6.13.2 Crank training equipment with speed dependent resistance system 17

7 Test report 17

Annex ZA (informative) Relationship between this European Standard and the safety requirements of Regulation 2023/988/EU aimed to be covered 18

Bibliography 21

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

ISO draws attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.

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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 83, "Sports and other recreational facilities and equipment".

This third edition cancels and replaces the second edition (ISO 20957-5:2016), which has been technically revised.

The main changes are as follows:

— formulation aligned with EN ISO 20957-1:2024;

— Clause 2 updated;

— Clause 3 modified to remove unused terms and definitions;

— “intrinsic loading” renamed to “loading”;

— “speed independent system” renamed to “speed independent resistance system” for clarity;

— “speed dependent system” renamed to “speed dependent resistance system” for clarity;

— Table 1 modified to allow Class B accuracy class products to display power in Watts;

— Table 2 modified to allow Class B accuracy class products to display power in Watts and to correct the section on maximum power;

— Annex A removed;

A list of all parts in the ISO 20957 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

This document concerns the safety of crank training equipment. It amends and supplements ISO 20957‑1:2024. The requirements of this document take priority over those in ISO 20957-1:2024.

Stationary training equipment — Part 5: Stationary exercise bicycles and upper body crank training equipment, additional specific safety requirements and test methods

This document specifies safety requirements for stationary exercise bicycles and upper body crank training equipment in addition to the general safety requirements of ISO 20957-1.

This document is applicable to stationary training equipment type stationary exercise bicycles and upper body crank training equipment (type 5) as defined in Clause 3 within the classes S, H, I and A, B, C according to ISO 20957-1.

Any attachment provided with the stationary exercise bicycles and upper body crank training equipment for the performance of additional exercises are subject to the requirements of ISO 20957-1.

This document is not applicable to roller stands as they cannot be made safe in a reasonable way.

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 4210‑8:2023, Cycles — Safety requirements for bicycles — Part 8: Pedal and drive system test methods

ISO 20957‑1:2024, Stationary training equipment — Part 1: General safety requirements and test methods

EN 71‑1:2014+A1:2018, Safety of toys — Part 1: Mechanical and physical properties

For the purposes of this document, the terms and definitions given in EN ISO 20957-1:2024 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

3.1

crank training equipment

stationary apparatus on which work is carried out by turning a crank mechanism either by using the lower body or the upper body or both

3.2

freewheel

mechanism which is designed to disengage the crank mechanism from the drive system in one direction

3.3

seat pillar

connection between the frame and the seat provided to adjust the height of the seat

3.4

seat tube

part of the frame where the seat pillar (3.3) is inserted

3.5

handlebar stem

connection between the frame and the handlebar provided to adjust the height of the handlebar

3.6

load adjustment

device to change the level of resistance felt by the user

3.7

constant power mode

programme that adjusts the equipment resistance level, allowing the user to maintain a selected, predetermined power level during the performance of the exercise, independent of pedalling revolutions per minute

Note 1 to entry:

3.9

adjustable handlebar

handlebars which can be adjusted for different training positions

3.10

seat system

system that consists of seat, seat back rest, adjustment and mounting components

The classification shall be according to ISO 20957‑1:2024.

NOTE Figure 1 to Figure 3 are intended only to give examples and to illustrate the names of the components.

Key

1 handlebar

2 display

3 hand grip

4 contact heart rate sensor

5 handlebar stem

6 handlebar height adjustment

7 frame

8 protective cover

9 pedal strap

10 transport wheel

11 pedal

12 power supply

13 foot

14 crank

15 flywheel

16 seat tube

17 seat height adjustment

18 seat pillar

19 horizontal seat adjustment

20 seat

21 load adjustment

22 handlebar adjustment device

23 heart rate belt

Figure 1 — Example of upright stationary exercise bicycle

Key

1 display

2 seat back rest

3 seat

4 seat handlebar

5 seat adjustment

6 frame

7 protective cover

8 crank

9 pedal

10 pedal strap

11 front handlebar

12 heart rate hand sensor

Figure 2 — Example of recumbent stationary exercise bicycle

Key

1 display

2 crank

3 handle

4 seat back rest

5 seat

6 vertical seat adjustment

7 horizontal seat adjustment

8 foot rest

9 frame

10 flywheel

11 protective cover

Figure 3 — Example of upper body crank training equipment

The following requirements shall apply, depending on the design of the crank training equipment.

The test finger shall not become entrapped and shall not come into contact with moving parts which do not have a smooth surface.

Where the diameter of the path of motion of the crank extends past the stationary parts of the construction (e.g. protective cover or frame), the distance between the pedal cranks and the stationary parts of the construction shall be ≥10 mm.

This requirement does not apply

a) in the area 50 mm from the axis of the crank;

b) if the diameter of the path of motion of the crank does not extend past the stationary parts of the construction.

If a flywheel is exposed, the exposed edges of the flywheel shall have a radius ≥2,5 mm.

Test in accordance with 6.1.1, 6.3.1 and 6.3.2.

Accessible parts of the crank training equipment shall not have a temperature greater than 65 °C.

Test in accordance with 6.2.

The crank training equipment shall withstand a load of 2,5 times the maximum user's body mass ±5 % as specified in the instructions for use or 2 500 N, whichever is greater. During the test, the crank training equipment shall not tip over and the slippage of the adjusted seat pillar into the seat tube shall be ≤5 mm.

Test in accordance with 6.4.1.

The handlebars shall withstand a load of 0,3 times the maximum user's body mass ±5 % specified in the instructions for use or (300 ± 15) N, whichever is greater for class H; for classes S and I, a load of 0,3 times the maximum user's body mass specified in the instructions for use or (450 ± 15) N, whichever is greater.

For recumbent bikes, the seat handlebars shall withstand a vertical load of 2,5 times the maximum user's body mass ±5 % specified in the instructions for use or 2 500 N, whichever is greater.

After the test, the training equipment shall not be broken or have visible signs of fracture or cracking and shall still function as intended.

Test in accordance with 6.4.2.

Pedals shall be in accordance with EN ISO 4210-8:2023.

After the test, the training equipment shall not be broken or have visible signs of fracture or cracking and shall still function as intended.

Test in accordance with 6.4.3.

The seat pillar shall have a permanent mark indicating the minimum insertion depth of ≥1,5 times the cross section reference dimension (e.g. diameter or longest diagonal use of a rectangular tube) into the seat tube. The mark is not required if the minimum insertion depth is given by the design.

Test in accordance with 6.1.1 and 6.1.2.

For classes S and I training equipment, the height adjustment system shall work without a tool.

For class H training equipment, if a tool is required to adjust the seat height, it shall be provided along with the equipment.

Test in accordance with 6.1.4.

The seat shall withstand a load of 2/3 times the maximum user's body mass as described in the instructions for use without tilting >2° from its position in relation to the seat tube. After the test, the training equipment shall not be broken or have visible signs of fracture or cracking and shall still function as intended.

Test in accordance with 6.5.

The handlebar stem shall be adjustable or different grip positions shall be provided.

If the vertical height is adjustable, the handlebar stem shall have a permanent mark indicating the minimum insertion depth of ≥1,5 times the cross section reference dimension (e.g. diameter or the longest diagonal of a rectangular tube). The mark is not required if the minimum insertion depth is given by the design.

Test in accordance with 6.1.1 and 6.1.2.

The crank training equipment shall not tip over.

Test in accordance with 6.7.

If the crank training equipment has upper and lower body rotational crank systems, there shall be a mechanism to disengage either the upper or lower crank when only one crank is in use.

Inadvertent entrapment of the hands and the fingers shall be prevented.

Test in accordance with 6.1.4.

The seat back rest shall withstand a load of

— 1 times the maximum user's body mass ±5 % specified in the instructions for use or 1 000 N, whichever is greater for class H, and

— 1,5 times the maximum user's body mass ±5 % specified in the instructions for use or 1 500 N, whichever is greater for classes S and I.

After releasing the load, the seat system shall not be broken and shall still function as intended.

Test in accordance with 6.6.

For speed independent resistance systems, classes A, B and C shall fulfil the requirements in accordance with Table 1. For speed dependent resistance systems, classes A, B and C shall fulfil the requirements in accordance with Table 2.

Table 1 — Classified requirements for speed independent resistance systems

Table 2 — Classified requirements for speed dependent resistance systems

The crank training equipment shall function properly as intended.

Test in accordance with 6.13.

In addition to the general instructions for use in EN ISO 20957‑1:2024, instructions for the safe use of crank training equipment including at least the following information, depending on the class, shall be provided:

a) adjustment of seat and handlebars;

b) indication of the minimum insertion depth of adjustable seat and adjustable handlebars;

c) adjustment of training resistance and power settings;

d) additional information, such as notes on the correct posture;

e) notice that class B and class C crank training equipment are not suitable for high accuracy purposes;

f) information on braking system (speed dependent resistance system or speed independent resistance system).

For classes B and C, a warning shall be placed on the equipment indicating that it is not suitable for high accuracy purposes: "WARNING — This stationary training equipment is not suitable for high accuracy purposes."

The measurement shall be done with appropriate measurement devices.

The visual examination shall be done under proper lighting.

The tactile examination shall be done without gloves.

The tested mechanism shall be actuated as specified in the instructions for use.

Apparatus: temperature measuring device with an accuracy of ±1 °C.

Pedal the training equipment at (200 ± 10) W with (60 ± 1) min^-1 for three periods of (20 ± 1) min. After each period, rest for (5 ± 1) min.

Within 2 min after the third period, measure the temperature of all exposed surfaces.

A test finger according to EN ISO 20957‑1:2024, shall be inserted parallel to the axis of rotation with a tolerance of ±5°, in contact with the crank and the stationary parts of the construction (e.g. protective cover or frame). The test shall be carried out in the most onerous position with the crank rotated fully in both directions. Determine whether the test finger becomes entrapped. If the angle allows the test finger to be pushed away, it is not considered to be an entrapment.

For class H, a test finger probe B in accordance with EN 71-1:2014+A1:2018 shall be approached from all sides to all moving parts other than the crank.

For class S and class I, a test finger according to EN ISO 20957‑1:2024 shall be approached to all moving parts other than the crank.

Determine whether the test finger becomes entrapped or whether it touches moving parts which are not smooth.

The crank training equipment shall be free standing on a flat surface. The seat pillar shall be adjusted as specified in the instructions for use to its most onerous position.

Mark the position of the seat pillar compared to the seat tube. Apply a test load as described in 5.5.1 with a (300 ± 5) mm × (300 ± 5) mm plate on the seat for 3 min. After the release of the test load, measure the slippage of the seat pillar.

Set the crank training equipment in a position to prevent tilting and/or slipping.

Adjust the front handlebars to their most onerous position.

For adjustable handlebars, if a screw is used to tighten, then apply a torque to the adjustment mechanism of

M = F · r

where

M is the torque to tighten the adjustment mechanism, in Newton metres;

F is the force of (140 ± 7) N;

r is the radius of the adjustment mechanism, in metres.

All other adjustment mechanisms shall be set as described in the instructions for use. For both adjustable and fixed front handlebars, load the handlebars with a (80 ± 5) mm wide band or sleeve. Apply the test load as described in 5.5.2 for (3 ± 1) min on the left or the right side in a direction which creates the highest torque moment applied to the adjustment mechanism.

For seat handlebars, apply 50 % of the test load as described in 5.5.2 simultaneously to each handle in the downward direction for (3 ± 1) min by using a (80 ± 5) mm wide band or sleeve.

The test shall be done according to EN ISO 4210‑8:2023, 4.1 and 4.6.3, but with the complete pedals and crank mounted to the frame of the crank training equipment.

The seat shall be fixed to the seat pillar in horizontal position. The seat pillar shall be fixed in the seat tube.

Apply a vertical test load, distributed over an area of 100 mm², on the lateral center line of the seat. First apply this vertical load (25 ± 5) mm from the front of the seat. Next apply this vertical load (25 ± 5) mm from the rear of the seat.

Arrange the test rig in such a way that the maximum torque is applied to the seat adjustment mechanism.

The duration of the test shall be (5 ± 1) min.

Set the crank training equipment in a position to prevent tilting and/or slipping.

Apply a horizontal load using a (300 ± 5) mm × (300 ± 5) mm plate on the lateral center line of the seat back rest, 50 mm below its upper edge, but positioned no higher than l = (500 ± 25) mm from the seat top, see Figure 4. Maintain this load for 3 minutes.

Key

1 plate, (300 ± 5) mm × (300 ± 5) mm

2 back rest

3 seat

l load application height

^a Horizontally applied load.

Figure 4 — Testing of seat back rest

Carry out the stability test according to ISO 20957‑1:2024 while operating the crank training equipment at (60 ± 6) min^-1 for >30 s.

The maximum error of the test device shall not exceed 2 % for values ≥100 W or 2 W for values <100 W. The maximum error of the rotational frequency shall not exceed 0,5 min^-1 for the measuring device.

The power is obtained by applying a drive to the crank axis.

Key

1 torque transducer

2 speed transducer

3 motor

Figure 5 — Test device for power, speed and torque measurement

Use the test device as shown in Figure 5. Set the crank training equipment to a constant power mode of (100 ± 5) W, displayed on the test device, with a speed of (50 ± 1) min^-1. Set the time (t) to 0. Change the speed to (90 ± 1) min^-1 within a maximum time of 5 s after t = 0. Measure the power once again 15 s after t = 0 with the test device, the power shall be

a) ±10 % of the power measured at t = 0 for class A, and

b) ±20 % of the power measured at t = 0 for class B.

Then reduce the speed to (70 ± 1) min^-1 and measure the power once again following the same procedure.

Repeat the test with a power level of (50 ± 2,5) W and (150 ± 7,5) W.

Set the crank training equipment to the heart rate control mode at a power of (150 ± 25) W or equivalent speed. Use a heart pulse simulator or a person to activate the control mode. Operate using the test device shown in Figure 5. Cut off the signal and then check that the power reduces according to the requirements shown in 5.9. If there are different heart rate control systems, each system shall be tested.

The mechanical power can be measured directly at the crank axis and a test device according to 6.8 shall be used.

Stationary exercise bicycles

Carry out the test as follows.

a) Pedal the crank training equipment for 1 h at the maximum power (resistance) at a speed of (60 ± 1) min^‑1.

b) Cool down the crank training equipment to room temperature.

c) Adjust the training equipment to (25 ± 2,5) W at (40 ± 1) min^‑1.

d) Compare the power of the test device with the power read out on the crank training equipment display.

e) Pedal for 15 min. After 15 min, measure the power and compare again to the reading on the display without stopping the crank training equipment.

f) Cool down the crank training equipment to room temperature.

Then carry out the above procedure with the following values by repeating steps c) to f):

— (50 ± 2,5) W at (50 ± 1) min^‑1;

— (100 ± 5) W at (50 ± 1) min^‑1;

— (150 ± 7,5) W at (60 ± 1) min^‑1;

— (200 ± 10) W at (60 ± 1) min^‑1;

— a non-tested free chosen value in the range of 25 W and 200 W at the speed between 40 min^‑1 and 80 min^‑1.

Upper body crank training equipment

Carry out the test as follows:

a) Pedal the crank training equipment for 1 h at the maximum power (resistance) at a speed of (60 ± 1) min^‑1.

b) Cool down the crank training equipment to room temperature.

c) Adjust the crank training equipment to (25 ± 2,5) W at (40 ± 1) min^‑1.

d) Compare the power of the test device with the power read out on the crank training equipment display.

e) Pedal for 15 min. After 15 min, measure the power and compare again to the reading on the display without stopping the crank training equipment.

f) Cool down the training equipment to room temperature.

Then carry out the above procedure with the following values by repeating steps c) to f):

— (50 ± 2,5) W at (50 ± 1) min^‑1;

— (75 ± 5) W at (60 ± 1) min^‑1;

— (100 ± 7,5) W at (70 ± 1) min^‑1;

— a non-tested free chosen value in the range of 25 W and 100 W at the speed between 40 min^‑1 and 70 min^‑1.

Carry out the test as follows.

a) Pedal the crank training equipment at a speed of (70 ± 1) min^‑1 for 1 h.

b) Cool down the crank training equipment to room temperature.

c) Pedal the crank training equipment at a speed of (40 ± 1) min^‑1.

d) Compare the power of the test device with the power read out on the crank training equipment display.

e) Pedal for 15 min. After 15 min, measure the power and compare again to the reading on the display without stopping the crank training equipment.

f) Cool down the crank training equipment to room temperature.

Carry out the above procedure for the following values by repeating steps c) to f):

— at (50 ± 1) min^‑1;

— at (60 ± 1) min^‑1;

— at (70 ± 1) min^‑1;

— a non-tested free chosen value in the range of 40 min^‑1 and 70 min^‑1.

Use a test device as in Figure 5 for measuring and setting speed and torque or speed and power.

Carry out the test as follows.

a) Operate the crank training equipment for at least 1 h at (100 ± 5) W at (60 ± 1) min^‑1. After conditioning, cool down the crank training equipment to room temperature.

b) Set the load adjustment system of the crank training equipment to the position so that the power is closest to 70 W when operated at (60 ± 1) min^‑1.

c) Measure the power within 30 s.

d) Set the load adjustment system of the crank training equipment to the position so that the power is closest to 200 W when operated at (70 ± 1) min^‑1.

e) Operate the crank training equipment for at least 15 min.

f) Return to the same measurement position as in point b).

g) Measure again the power within 30 s.

Compare the values measured in c) and g). The value in g) shall not vary by more than ±20 % of the value in c).

Subject the crank training equipment to an interval test (10 min loading, 5 min cooling down) for ≥2 h at the closest setting that is ≥80 % of the maximum power at (60 ± 1) min^-1.

After the test, the training equipment shall not be broken or have visible signs of fracture or cracking and shall still function as intended.

Subject the crank training equipment to an interval test (10 min loading, 5 min cooling down) for ≥2 h at (100 ± 1) min^-1.

After the test, the training equipment shall not be broken or have visible signs of fracture or cracking and shall still function as intended.

The test report shall include at least the information according to ISO 20957‑1:2024 and a reference to this document, i.e. ISO 20957‑5, and ISO 20957‑1:2024.

Annex ZA
(informative)

Relationship between this European Standard and the safety requirements of Regulation 2023/988/EU aimed to be covered

NOTE Annex ZA is not included in the final ISO publication.

This European Standard has been prepared under a Commission’s standardization request Standardisation mandate issued to the European standardisation organisations (ESOs) to develop European standards for stationary training equipment “M/506” to provide one voluntary means of conforming to the safety requirements of Commission Decision (EU) No 476/2011 of 27 July 2011 implementing General Product Safety Regulation 2023/988/EU of the European Parliament and of the Council with regard to safety requirements for stationary training equipment.

Once this standard is cited in the Official Journal of the European Union under that Regulation 2023/988/EU, compliance with the normative clauses of this standard given in Table ZA.1 confers, within the limits of the scope of this standard, a presumption of conformity with the corresponding safety requirements of that Directive and associated EFTA regulations.

Table ZA.1 — Correspondence between this European Standard and Commission Decision (EU) No 476/2011 of 27 July 2011 implementing Regulation 2023/988/EU of the European Parliament and of the Council with regard to safety requirements for stationary training equipment and Commission’s standardization request Standardisation mandate issued to the European standardisation organisations (ESOs) to develop European standards for stationary training equipment ‘M/506’

WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European Standard is maintained in the list published in the Official Journal of the European Union. Users of this standard should consult frequently the latest list published in the Official Journal of the European Union.

WARNING 2 — Other Union legislation may be applicable to the products falling within the scope of this standard.

Bibliography

[1] Regulation (EU) No 2023/988 (General Product Safety Regulation)

[2] ISO 12100, Safety of machinery — General principles for design — Risk assessment and risk reduction

[3] ISO 13732‑1, Ergonomics of the thermal environment — Methods for the assessment of human responses to contact with surfaces — Part 1: Hot surfaces