B--Draft Standards for Elliptical Trainers and Stationary Cycles Request for Information

REQUEST FOR INFORMATION This is a Request for Information (RFI) for OPNAV, N135, Millington, TN. This RFI concerns the Draft Standards for Elliptical Trainers and Stationary Cycles. This RFI does not constitute an Invitation for Bid, a Request for Proposal, or commitment of any kind by the U.S. Navy. There will be no reimbursement or compensation provided for responding to this RFI. DRAFT STANDARD FOR ELLIPTICAL TRAINERS BACKGROUND The U.S. Navy currently allows use of an elliptical trainer as one testing mode for aerobic capacity in its semiannual Physical Readiness Test (PRT). The test is administered as follows: The test-taker is given a suitable opportunity to warm up prior to testing. This warm-up may take place on the trainer or somewhere else prior to getting on the trainer. The test then consists of a 12-minute exercise bout on the trainer at a resistance and pedaling speed of the test-taker’s choosing. At the end of the bout, the number of kilocalories expended is recorded and used in conjunction with the test-taker’s weight to predict an equivalent 1.5-mile run time. The twelve minute test period may be changed at some future date. The Navy Physical Readiness Program desires that elliptical trainers used for testing be interchangeable so that equivalent performances on any trainer lead to equivalent run time predictions. One way to achieve this goal is to standardize the accuracy with which kilocalories expended are estimated from braking force/power at the flywheel. This performance standard defines machine parameters for elliptical trainers that will lead to such equivalent performances. GENERAL To qualify for Navy PRT use, 1. The elliptical trainer must be constructed and operate in conformance with ISO Standards 20957-1 and 20957-9 (EN-957-1 & EN-957-9). 2. The elliptical trainer must conform to usage class S, professional and/or commercial use. 3. The elliptical trainer must provide a speed-dependent exercise mode in which a fixed braking power is provided and the work performed varies with the stride frequency. 4. The elliptical trainer must provide moveable handlebars in addition to the foot-platform pedals as a means of applying exercise torque to the flywheel. 5. The elliptical trainer must not have a variable incline, or if the elliptical trainer is equipped with a variable incline, the incline is set in a pre-defined angle during the test and the controls for adjusting the incline are disabled. The user will not be allowed to alter the angle of the variable incline once the test begins. At the beginning of the test, the variable incline is set to a pre-determined angle that provides accurate calorie counting for the effort. 6. The elliptical trainer must not have a variable stride length. The fixed stride length must be between 18.0 and 21.5 inches. 7. The elliptical trainer must have an accurate calorie counter. The standard for accuracy is the agreement of the calories reported by the elliptical trainer with calories calculated from measured rates of oxygen consumption during exercise on the device. A validation study must be conducted to demonstrate suitable accuracy of the elliptical trainer calorie counts. The devices will be deemed suitably accurate if (1) the 95% confidence interval for the slope of the regression of measured calories on device-indicated calories includes the value 1, and (2) the difference between the mean value of the measured calories and the mean value of the indicated calories lie in the range of -30 to +30 kcal for a 12 minute period. Parameters of the validation study are: (1) it must include at least 75 comparisons of measured and indicated calories, (2) the measurements must be distributed over the range of 100 to 350 kilocalories in 12min, and (3) recording of measured calories can only be made after at least 3 minutes of exercise at the chosen load. This is done to allow the rate of oxygen consumption to stabilize at that load. 8. The validation study must be conducted by an outside agent, not by the elliptical trainer manufacturer. TEST OPERATION The elliptical trainer needs to support a test in which the test duration (currently 12:00 min) can be entered at the console at the start of the test. A “start? button is pressed and energy expenditure in calories is accumulated for the specified time. At the end of the specified time period, the number of calories expended is saved and held on the display, and the test participant is allowed to continue pedaling to cool down. Calories expended during warm-up or cool down are not added to the calories expended during the test. Specific requirements are: 1. The test participant must be able to vary the resistance and stride rate during the test and during warm-up and cool down periods. 2. The elliptical trainer needs to provide at least 450W of braking power at the input crank shaft. 3. The elliptical trainer needs to have a “timer? function to provide a fixed-duration exercise test. Warm-up periods shall not be included in the “Navy Test?. Timing should be accurate to the nearest 0.5 second. The test can allow for warm up with a prompt “Press Start? to begin the test? 4. A button (or other control) to begin the “Navy Test? needs to be provided. This can be a dedicated button labeled “Navy Test?, or can it be a multi-function button with “Navy Test? as one of the options? Pressing this button should reset the machine, put the elliptical in speed-dependent mode and prompt the user (either test-taker or test administrator) to enter the test duration in minutes and seconds and body weight in pounds to the nearest whole pound. 5. Test time and body weight (to the nearest whole pound) must remain locked and displayed until the button to begin the test is pressed. This allows the test administrator to confirm the entries. 6. A clearly marked “Begin Test? button (or other control) must be provided on the console. This button can be a dedicated button labeled “Begin Test?, or can it be a button labeled “Quick Start? with a prompt in the display stating “Press Quick Start to begin test?, or some similar prompt. It should be placed so that either the test-taker or the test administrator can actuate it. 7. Once the “Begin Test? button has been pushed, the elliptical trainer display must indicate cumulative kilocalories expended during the test to the nearest whole kilocalorie. The trainer must also provide a continuous display of the elapsed time in minutes and seconds to the nearest second, the resistance level and the stride rate or revolution∙min-1 (RPM) to the nearest RPM. Body weight in pounds must be displayed at the end of the test for test administrator. 8. The elliptical trainer needs to calculate, update and display the sum of the kilocalories expended during the exercise bout at a rate of at least 1 sample∙second-1. At any time, the sum displayed must be the cumulative sum of all calories expended rounded to the nearest whole kilocalorie excluding kilocalories expended during warm-up and cool-down. 9. The elliptical trainer needs to retain and display the cumulative kilocalories and the body weight at the end of the timed exercise bout. These values must remain fixed on the display while the machine allows the test participant to continue striding, even at a different stride rate and/or resistance for a cool down. 10. The accumulated kilocalories, the body weight (lb) and the test time should remain on the display until cleared by the test operator. 11. The clock must run continuously from the beginning until the end of the test period even if the test taker stops exercising. The calories displayed will be the total for the specified test period, including the stopped interval. If the machine is self-powered, the display must remain on at least 1 minute following the cessation of exercise by the test-taker. 12. A test interrupt function needs to be provided to allow either the test-taker or the test administrator to stop the test prior to the finish. If interrupted, the calories are not saved or displayed. 13. At the end of the test, a button (or other control) needs to be provided to clear the display and provide a prompt to perform another test or quit testing, or return to the menu from which the test is launched. 14. Indicating the intent to conduct another test should clear the display and prompt for test duration and body weight again. 15. Indicating that testing is at an end should clear the display and put the elliptical trainer back in its basic start up mode. 16. There shall be no indication on the elliptical trainer from the manufacturer that it is approved for the U.S. Navy test. 17. The elliptical trainer shall not contain an algorithm to predict a run time or Navy PRT score from calorie expenditure. Navy prediction models are subject to change, and differences in precision between the onboard processor and the Navy calculation methods lead to results that do not match Navy calculations closely enough. DRAFT STANDARD FOR STATIONARY CYCLES BACKGROUND The U.S. Navy currently allows use of a stationary cycle as one testing mode for aerobic capacity in its semiannual Physical Readiness Test (PRT). The test is administered as follows: The test-taker is given a suitable opportunity to warm up prior to testing. This warm-up may take place on the cycle or somewhere else prior to getting on the cycle. The test then consists of a 12-minute exercise bout on the cycle at a resistance and pedaling speed of the test-taker’s choosing. At the end of the bout, the number of kilocalories expended is recorded and used in conjunction with the test-taker’s weight to predict an equivalent 1.5-mile run time. The twelve minute test period may be changed at some future date. The Navy Physical Readiness Program desires that stationary cycles used for testing be interchangeable so that equivalent performances on any trainer lead to equivalent run time predictions. One way to achieve this goal is to standardize the accuracy with which kilocalories expended are estimated from braking force/power at the flywheel. This performance standard attempts to define performance parameters for stationary cycles that will lead to such equivalent performances. GENERAL To qualify for Navy PRT use, 1. The stationary cycle must be constructed and operate in conformance with ISO Standards 20957-1 and 20957-5 (EN-957-1 & EN-957-5). 2. The stationary cycle must conform to usage class S, professional and/or commercial use. 3. The stationary cycle must provide a speed-dependent training mode in which a fixed braking power is provided and the work performed varies with the pedaling frequency. 4. The stationary cycle must have an accurate calorie counter. The standard for accuracy is the agreement of the calories reported by the stationary cycle with calories calculated from measured rates of oxygen consumption during exercise on the device. A validation study must be conducted to demonstrate suitable accuracy of the stationary cycle calorie counts. The devices will be deemed suitably accurate if (1) the 95% confidence interval for the slope of the regression of measured calories on device-indicated calories includes the value 1, and (2) the difference between the mean value of the measured calories and the mean value of the indicated calories lie in the range of -30 to +30 kcal for a 12 minute period. Parameters of the validation study are: (1) it must include at least 75 comparisons of measured and indicated calories, (2) the measurements must be distributed over the range of 50 to 200 kilocalories in 12min, and (3) recording of measured calories can only be made after at least 3 minutes of exercise at the chosen load. This is done to allow the rate of oxygen consumption to stabilize at that load. 5. The validation study must be conducted by an outside agent, not by the stationary cycle manufacturer. TEST OPERATION The stationary cycle needs to support a test in which the test duration (currently 12:00 minutes) and body weight in pounds are entered at the console. A “start? button is pressed and energy expenditure in calories is accumulated for the specified time. At the end of the specified time period, the number of calories expended is saved and held on the display, and the test participant is allowed to continue pedaling to cool down. Calories expended during cool down are not added to the calories expended during the test. Specific requirements are: 1. The test participant must be able to vary the resistance and RPM during the test and any cool down after the test. 2. The stationary cycle needs to provide at least 450W of braking power. 3. The stationary cycle needs to have a “timer? function to provide a fixed-duration exercise test. Warm-up periods shall not be included in the “Navy Test?. Timing should be accurate to the nearest 0.5 second. 4. A button (or other control) to begin the “Navy Test? needs to be provided. Pressing this button should reset the machine, put the cycle in speed-dependent mode and prompt the user (either test-taker or test administrator) to enter the test duration in minutes and seconds and body weight in pounds. 5. Test time and body weight (to the nearest whole pound) must remain displayed until the button to begin the test is pressed. This allows the test administrator to confirm the entries. 6. A clearly marked “Begin Test? button (or other control) must be provided on the console. It should be placed so that either the test-taker or the test administrator can actuate it. 7. Once the “Begin Test? button has been pushed, the stationary cycle display must indicate cumulative kilocalories expended during the test to the nearest whole kilocalorie. The trainer must also provide a continuous display of the elapsed time in minutes and seconds to the nearest second, body weight in pounds, the resistance level and the pedaling rate to the nearest revolution∙min-1. 8. The stationary cycle needs to calculate, update and display the sum of the kilocalories expended during the exercise bout at a rate of at least 1 sample∙second-1. At any time, the sum displayed must be the cumulative sum of all calories expended rounded to the nearest whole kilocalorie. 9. The stationary cycle needs to retain and display the cumulative kilocalories and the body weight at the end of the timed exercise bout. These values must remain fixed on the display while the machine allows the test participant to continue pedaling, even at a different stride rate and/or resistance for a cool down. 10. The accumulated kilocalories, the body weight (lb) and the test time should remain on the display until cleared by the test operator. 11. If the test taker stops exercising, the clock must continue to run until the end of the test period. The calories displayed will be the total for the test period, including the stopped interval. 12. A test interrupt function needs to be provided to allow either the test-taker or the test administrator to stop the test prior to the finish. If interrupted, the calories are not saved or displayed. 13. At the end of the test, a button (or other control) needs to be provided to clear the display and provide a prompt to perform another test or quit testing. 14. Indicating the intent to conduct another test should clear the display and prompt for test duration and body weight again. 15. Indicating that testing is at an end should clear the display and put the stationary cycle back in its basic start up mode. 16. There shall be no indication on the stationary cycle from the manufacturer that it is approved for the U.S. Navy test. 17. The stationary cycle shall not contain an algorithm to predict a run time or Navy PRT score from calorie expenditure. Navy prediction models are subject to change, and differences in precision between the onboard processor and the Navy calculation methods lead to results that do not match Navy calculations closely enough. Vendors interested in submitting elliptical trainers and/or stationary bikes for official PFA testing consideration should contact LCDR D. D. Peterson, OPNAV N135F Research Officer, at +1 (555) 000-0000 or via email at contact@example.gov. Include in the email Subject line: RFI for Draft Standards NOTE: Packages submitted to the Navy will not be returned.