This Day On The Street
Continue to site
This account is pending registration confirmation. Please click on the link within the confirmation email previously sent you to complete registration.
Need a new registration confirmation email? Click here

New Study: Adaptive Motion Trainers Can Put Significant Stress On Knees, May Not Be Best Option For Those With Knee Pain

New research conducted by the University of Wisconsin - La Crosse Department of Physical Therapy calls into question the conventional wisdom that non-impact cardio machines, such as adaptive motion trainers (AMTs), apply minimum stress to the joints. The study shows that some cross trainers, particularly ones that move in an elliptical-like pattern, may still impose high stresses on the knee. The research was funded by the Cybex Research Institute (CRI), research division of Cybex International Inc. (NASDAQ: CYBI).

“What we’re learning is that shock is not the only relevant factor in reducing knee stress,” said Dr. Paul Juris, executive director of CRI. “Even in low or non-impact motion, compression at the patellofemoral joint – just under the kneecap – can be significant. With millions of people suffering from knee pain, this research comes at a critical time.”

Important Facts:
  • Anterior knee pain is the most common complaint among physically active adults and children and accounts for 62% of all knee injuries. 1
  • Patellofemoral Pain Syndrome (PFPS) accounts for 57% of all knee problems in runners. 2.5 million runners are diagnosed with PFPS in a calendar year. 2

As the problem persists, people are migrating to non-impact forms of exercise like ellipticals and AMTs assuming that it's a safe alternative. However this new research shows that non-impact cross trainers are not stress-free, and that patellofemoral stress occurs at levels significantly greater on some devices than on others.

In the University of Wisconsin study, 16 subjects exercised at 75% of their age-predicted maximum heart rate on the Cybex Arc Trainer and Precor AMT cross trainer, at a constant pace of 100 steps per minute. An instrumented foot plate measured pedal reaction forces and an eight-camera infrared motion capture system measured pedal position, body position, and joint angles. Based on this information, peak patellofemoral joint forces (PFJFs), measured in Newtons per kilogram (N/kg), were calculated to be 141 percent greater on the AMT compared to the Arc Trainer. While the values for the AMT (19 N/kg) were comparable to that of stair climbing (21 N/kg) and lunging (19 N/kg), the Arc Trainer (8 N/kg) was more comparable to walking (9 N/kg). The Arc Trainer allowed users to maintain a high-level workout with PFJFs less than half that of the AMT.

1 of 3

Check Out Our Best Services for Investors

Action Alerts PLUS

Portfolio Manager Jim Cramer and Director of Research Jack Mohr reveal their investment tactics while giving advanced notice before every trade.

Product Features:
  • $2.5+ million portfolio
  • Large-cap and dividend focus
  • Intraday trade alerts from Cramer
Quant Ratings

Access the tool that DOMINATES the Russell 2000 and the S&P 500.

Product Features:
  • Buy, hold, or sell recommendations for over 4,300 stocks
  • Unlimited research reports on your favorite stocks
  • A custom stock screener
Stocks Under $10

David Peltier uncovers low dollar stocks with serious upside potential that are flying under Wall Street's radar.

Product Features:
  • Model portfolio
  • Stocks trading below $10
  • Intraday trade alerts
14-Days Free
Only $9.95
14-Days Free
Dividend Stock Advisor

David Peltier identifies the best of breed dividend stocks that will pay a reliable AND significant income stream.

Product Features:
  • Diversified model portfolio of dividend stocks
  • Updates with exact steps to take - BUY, HOLD, SELL
Trifecta Stocks

Every recommendation goes through 3 layers of intense scrutiny—quantitative, fundamental and technical analysis—to maximize profit potential and minimize risk.

Product Features:
  • Model Portfolio
  • Intra Day Trade alerts
  • Access to Quant Ratings
Real Money

More than 30 investing pros with skin in the game give you actionable insight and investment ideas.

Product Features:
  • Access to Jim Cramer's daily blog
  • Intraday commentary and news
  • Real-time trading forums
Only $49.95
14-Days Free
14-Days Free


Chart of I:DJI
DOW 17,812.19 +19.51 0.11%
S&P 500 2,089.14 +2.55 0.12%
NASDAQ 5,102.8080 +0.33 0.01%

Free Reports

Top Rated Stocks Top Rated Funds Top Rated ETFs