
You are experiencing with
what we call a "plateau" and while it is not uncommon, I understand that it can
be frustrating. At this point, increasing the intensity of your workouts is what
will make the difference. For instance, if you are currently walking three days
a week for thirty minutes at 3.5 mph with a 1.0 % grade, increase your speed to
3.7 mph and increase your grade to 2.0%. Depending on where you're at now, this
may seem like a very minor or a very major increase, but it is just to offer a
guide on furthering aerobic progression.
You may also want to consider
a different activity for one of your three workouts. If you bike three times per
week, try walking or using a stair climber one day each week instead.
For strength training, increasing
intensity is also key. Make sure you are fully challenging your muscles—you should
only be able to complete eight to twelve repetitions before needing a rest. Also,
swapping out old strengthening exercises and adding new ones will help by challenging
your muscles in a new way. There are several exercises available for working the
same muscle groups and a fitness instructor, exercise video or well-illustrated
book can provide new ideas.
Remember that when you reach
a plateau, you will eventually overcome it and start progressing again, but it
is critical to persevere and stick with your program to enjoy those later successes.