This is the time of year when many outdoor exercisers transition to indoor aerobic activities. Once the temperature falls below 50 degrees, bicycling becomes less pleasant; temperatures below 40 degrees convince many runners to seek indoor alternatives.

Although outdoor endurance exercise is more interesting, there are several ways to make indoor aerobic activity less boring and more beneficial. You can, of course, watch television, listen to music, or read the paper while you ride the stationary cycle. But you might also consider cross-training, circuit training and interval training, all of which have significant advantages over standard, steady-state exercise.

Standard, steady-state exercise

Most aerobic exercisers follow a consistent pattern of training, known as standard, steady-state exercise. A typical training session begins with a few minutes of the aerobic activity (cycling, running, etc.) at an easy level. This provides a warm-up for both the cardiovascular system and the muscles involved in the endurance exercise. The warm-up segment is followed by a 20- to 30-minute period of continuous, moderate-effort exercise that elevates heart rate to approximately 75 percent of maximum. This is the steady-state component of the exercise session; it provides the cardiovascular conditioning effect. The steady-state period is followed by a reduced-effort cooldown segment, lasting about three to five minutes, or until heart rate is within 20 beats per minute of resting level.

Steady-state endurance exercise is effective for increasing cardiovascular endurance, but there are alternative aerobic activities that offer a lower risk of muscle overuse/imbalance injuries and provide a greater cardiovascular training effect. Just as important, they are more interesting to perform.

Cross-training

Rather than spending 30 minutes on a single exercise, try performing three successive aerobic activities for 10 minutes each. For example, a cross-training session could consist of a few minutes walking to warm up, then 10 minutes of stationary cycling, 10 minutes of elliptical exercise, and 10 minutes of stair stepping, followed by a few minutes of walking to cool down. By changing exercises, you reduce the risk of muscle overuse/imbalance injuries that often result from performing the same movement pattern every workout.

Also, by using different muscle groups for different exercises, cumulative fatigue is reduced and your performance level may increase. The following aerobic activities could be part of a cross-training program: recumbent cycling, upright cycling, treadmill walking, treadmill running, elliptical training, stair stepping, stair climbing, rowing and rope jumping.

Circuit training

Circuit aerobic training is similar to cross-training, but it involves a more systematic exercise selection/sequence and much shorter activity segments. Successive exercises emphasize different muscle groups so that some muscles are resting while others are working. Because successful circuit training requires relatively high effort levels throughout the workout, each exercise is performed for just three to five minutes at a time. Consider this sample program for a 32-minute session: walking warm-up (four minutes), recumbent cycling (four minutes), treadmill jogging (four minutes), rowing (four minutes), elliptical training (four minutes), upright cycling (four minutes), stair climbing (four minutes), walking cool-down (four minutes). In addition to the physical benefits of performing seven different exercises, the brief training segments make circuit aerobic workouts more interesting from a mental perspective.

Interval training

The most challenging and productive form of aerobic activity is called interval training. Whether you are a beginning exerciser or an advanced athlete, interval training is the most effective means for improving your present level of cardiovascular fitness. The basic principle of interval training is alternating periods of higher-effort exercise and lower-effort exercise.

Let’s say that you normally ride the stationary cycle at 50 watts for your three-minute warm-up and cool-down segments, and at 100 watts for your 20-minute steady-state period. Do the same warm-up and cool-down protocol, but divide your steady-state period into seven intervals of three minutes each. Cycle your first, third, fifth and seventh three-minute intervals at 125 watts (higher-effort training), and cycle your second, fourth and sixth three-minute intervals at 75 watts (lower-effort training). You should see results after as little as three weeks of interval training, especially if you perform at least two interval training sessions per week.

Wayne L. Westcott, Ph.D., teaches exercise science at Quincy College and consults for the South Shore YMCA. He has written 24 books on fitness.

Looking for a fitness buddy? Get a dog – Health – msnbc.com

When it comes to getting fit a person’s best friend just might be a four-legged one.

Looking for a fitness buddy? Get a dog

Sergei Karpukhin  /  REUTERS

A dog catches a frisbee during the Russian dog frisbee championship in Moscow August 7, 2011. Dogs and their owners took part in a variety of distance and accuracy competitions during the championship to test their frisbee skills. REUTERS/Sergei Karpukhin

NEW YORK — When it comes to getting fit a person’s best friend just might be a four-legged one.

Experts say studies show dog owners walk more, walk faster, and are more likely to enjoy an active lifestyle because of their companion animal.

“I’m fascinated by what a great motivator dogs can be,” said Dr. Sandra McCune, co-editor of the book, “The Health Benefits of Dog Walking for People and Pets.”

McCune, an animal behaviorist based in Leicestershire, England, said studies show if you’re a dog walker, you’re more likely to meet the guidelines for daily activities.

Dogs are the reason behind two-thirds, 66 percent, of the walks their owners take each week, according to a recent survey of more than 1,011 adults commissioned by pet food company Mars Petcare.

One-quarter of people with children and pets regularly visit parks and other outdoor spaces because of their dog.

“Personally, I have a Labrador,” McCune said. “When it’s dark, when it’s raining, the dog needs a walk, every day.”

She said dog walking also strengthens social and communal ties.

“If people go out with a dog, they’re more likely to have a conversation,” she explained.

According to the poll some 44 percent of dog owners aged 65 and older exercise on a weekly basis because of their dog.

“Dogs are strong drivers of social capital,” said McCune, explaining that social capital is a sociological term which she defined as the value of all relationships.

“Dog ownership benefits the entire community,” she said.

This fall YMCAs in several U.S. cities are hosting their version of dog days. Called the Power of Pets, the programs include dog run/walks, dog yoga and other dog fair activities.

“It’s a chance to get the community together,” Katy Leclair, executive director of the Lake View, Illinois YMCA said of the program. “Families with dogs tend to be more active.”

As workout partners, canines can offer energy, enthusiasm, and the social support so crucial to sticking with an exercise program, according to Shirley Archer, spokesperson for the American Council on Exercise.

“Dogs can provide that companionship,” said Archer, a Florida-based fitness instructor. “Frisbee tossing, ball throwing, agility competitions, dog and human boot camps, are great opportunities to be active,” she said. “But obedience training is a must.”

She cautions that as living creatures dogs need to be taken care of.

“If they ride with you on a bicycle, they need to be trained to stay close,” she said. “Keep them hydrated. Check their paws. Don’t let them run right after they eat.”

Laura Cartwright Hardy, a grandmother and full-time graduate student living in Little Rock, Arkansas, has two huge German Shepherds.

“I’ve had big dogs since I was 20 and that’s definitely been part of the reason I’ve always been fit,” said Hardy, who started lifting weights in her 30s so she could carry 40-pound (18.14-kg) bags of dog food with ease.

“They certainly keep you honest about walking,” she said. “Those big brown eyes make it impossible to say no.”

She added that every human walking partner she has had, except her sister and her husband, quit because she went too fast.

“My dogs (all girls) have been steadfast,” she said.