At 66 years of age I still work out 1/2 hour a day from November through the end of March on an inclined treadmill. Instead of stimulating twitch muscles, I use it to build endurance. Blowing out a knee is not a concern. The motion is all straight ahead. It allows this old man to walk 18 holes of golf pulling his cart without feeling any fatigue. No one can convince me that such conditioning would not be helpful to linemen come the 4th quarter.