Grow With Cardio

Most guys pay lip service to including aerobics and strength exercise in their training programs, but the majority gravitate to one form or the other. Hardcore runners, for example, will push some weights from time to time and guys with big bench presses will take a few laps, but that’s usually the exception rather than the rule. New research shows that if you like to lift weights, you don’t have to have the body of a marathon runner to get the benefits of aerobics. In fact, doing the right kind of cardio will help you gain muscle mass.

Advances in genetics and biochemistry have shown us that it’s possible to build muscle and aerobic capacity at the same time. Even better, you can get a complete strength and cardiovascular workout in about 40 minutes. This is no “get fit without cost” training program. It is difficult and it hurts, but you can build muscle while maximizing cardiovascular capacity.

Grow with Cardio

Until recently, exercise recommendations from professional organizations such as the American College of Sports Medicine (ACSM) and the American Heart Association emphasized aerobics and only included strength training as an afterthought. In the past 10 years, scientists discovered that strength training had a huge effect on metabolic health and provided many of the same benefits as aerobics.

Some of the benefits of weight training include increased resting metabolic rate, improved blood sugar control and blood fat profiles, decreased gastrointestinal transit time (reducing the risk of colon cancer), reduced resting blood pressure, increased bone density and muscle mass, fewer symptoms from arthritis, reduced risk of low back pain, improved flexibility, and increased aerobic capacity. Since these are many of the same benefits of aerobics, combining aerobic and resistive exercise methods might provide the best of both worlds— improved metabolic health and increased muscle mass.

Conventional wisdom among many athletes and coaches is that you must lift heavy weights to get big and strong. Sophisticated biochemical studies on muscle protein synthesis show that this isn’t true. Training at intensities close to momentary muscle failure causes greater increases in muscle size than practicing high-weight, low-rep training programs. These studies showed that gains were sometimes twice as great from using momentary muscle failure training methods as training with heavy weights for fewer reps.

When exercising to increase muscle growth, your goal should be to activate all the motor units within a muscle group, which maximizes the stimulus that forces muscle fibers to increase in size. A motor unit consists of a nerve from the spine connected to muscle fibers. The principle fiber types in humans are Type I, IIa, and IIx. Type I fibers are used first, followed by the IIa and IIx fibers in response to fatigue or heavier loads.

New genetic and biochemical studies on muscle growth showed that muscle protein synthesis is best using a combination of muscle overload and aerobics. The nucleus is the center for protein synthesis in cells throughout the body. Skeletal muscle cells are unique because they contain more than one nucleus. Muscle cells increase cell nuclei by generating satellite cells in response to cell damage and muscle tension caused by weight training. This increases the capacity for muscle hypertrophy in the future and helps trained muscles maintain increased size.

The body tries to maintain a balance that scientist call homeostasis. For example, try to lose weight rapidly and metabolic control mechanisms increase appetite and slow metabolic rate. Muscle size also has a balance control. A chemical called myostatin prevents muscles from getting too large. It is balanced by follistatin, which promotes muscle growth.

Danish scientists showed that the liver increases follistatin output and decreases myostatin during and shortly after aerobic exercise. They also found that intense training with light loads increased satellite cells as well as heavier loads. Intense aerobics and muscular overload exercise also increase blood levels of growth hormone and IGF-1, both of which are critical for promoting muscle growth. The workout in this article combines high-intensity interval training and kettlebell training, which boost fitness and increase muscle mass.

High-Intensity Aerobics and Kettlebell Training Increase Muscle Mass and Cardiovascular Fitness

High-Intensity Aerobic Training (HIIT)

Roger Bannister broke the four-minute mile in 1952, running about two miles during each training session. He used high-intensity interval training methods developed by Eastern European, Australian, and British coaches.

Short bouts of maximal-intensity exercise build high levels of fitness quickly. Canadian researchers found that six sessions of high-intensity interval training on a stationary bike increased muscle oxidative capacity (citrate synthase) by almost 50 percent, muscle glycogen (stored carbohydrate) by 20 percent, and cycle endurance capacity by 100 percent. The subjects made these amazing improvements exercising a mere 15 minutes in two weeks.

A follow-up study in moderately-active women using the same training method showed that interval training increased whole-body and skeletal muscle capacity for fat use during exercise. A third study compared traditional endurance training (training on a stationary bike for 60-90 minutes per workout) versus interval training (6 sets, 30 seconds at maximum intensity, with four minutes rest between sprints). Improvements in fitness and biochemical factors were nearly identical. The key element in all three studies was training at 100 percent of maximum effort. These studies showed the importance of high-intensity training for building aerobic capacity and endurance.

The body uses different biochemical pathways to help it adapt to endurance or strength training. Guys training to look buff try to develop large, symmetrical muscles and minimize fat. Unfortunately, these processes often work against each other— low-calorie diets and aerobic exercise can compromise muscle growth. Muscle hypertrophy requires muscle tension, anabolic hormones, amino acids, calories, and adequate recovery. This environment activates signaling mechanisms inside the cells that turns on protein synthesis and builds muscle.

Athletes cut fat through a combination of low-calorie diets and endurance exercise, both of which can compromise protein synthesis and muscle growth. Usually, training simultaneously for muscle growth and endurance compromises muscle hypertrophy. Strength and endurance training initiate different signaling pathways within the muscle cells. Endurance training activates AMPK— an important energy-sensing enzyme that monitors cellular energy status. AMPK inhibits mTOR, a cell-signaling chemical that promotes muscle protein synthesis and muscle hypertrophy.

Short-duration, intense muscular exercise is typically associated with resistance training that turns on cell biochemical pathways in muscle that stimulate growth. Canadian scientists found that high-intensity interval exercise training (HIIT) caused rapid cellular and cardiovascular changes that resemble traditional endurance training. HIIT did not, however, turn off signaling pathways that stimulate muscle protein synthesis and growth.

Practice the high-intensity interval training workout three days per week. You can do the kettlebell and HIIT workouts on the same day, but the workout is challenging. For HIIT, the elliptical or stationary bike is best, but you could also use a Stairmaster or stair climber machine.

HIIT for Elliptical Trainers

Elliptical trainers are great for interval training because you can train intensely without beating up your knees, hips, and back. Interval training on this machine varies the striding speed, resistance, and ramp height. For beginners, a basic program is to alternate between fast and slow striding rates. For example, set the ramp and resistance at low levels (1-5) and “run” for two minutes at 70 strides per minute (spm). Alternate between one minute at 110 spm and one minute at 70 spm. Begin with 5 intervals and increase them as you become more fit.

When you can do 10 one-minute intervals at 80 percent effort, you are ready for the HIIT program on the elliptical trainer: 6 to 8 sets of 30 seconds at top stride speed, maximum ramp height (high knees), at the heaviest load you can maintain, at least 100-150 spm with four minutes rest between intervals. You must work at maximum intensity to get the full benefit!

HIIT for Stairclimbing Machines

HIIT routines for the stairclimber are similar to those of the elliptical trainer— you vary the resistance and stepping rate. An example of a beginning routine is to set the resistance at a low level and work at a step rate of 50-60 steps per minute (spm) for two minutes. Alternate between one minute at 80-90 spm and one minute at 50-60 spm. When you can do 10 intervals at 80 percent effort, you are ready for the HIIT workout on the stairclimber: 6 to 8 sets of 30-second intervals at 100 percent effort, with four minutes rest between intervals.

HIIT for Stationary Bikes

If you are a beginner, ride at an intense pace for 10 to 15 sets of two minutes, with one to two minutes rest between sets. When you can complete 15 sets, you are ready for the stationary bike HIIT workout: On the stationary or supine bike, sprint as fast as you can for 30 seconds, rest for four minutes, and then repeat six to eight times. High-intensity interval training builds aerobic capacity quickly, and the key is to exercise at maximum intensity.

Kettlebell Training

Combining HIIT with kettlebell training builds muscle and endurance at the same time. Kettlebell training uses high speed, ballistic motions that derive power from the hips and legs, while sparing and stabilizing the back. Whole-body movements require carefully choreographed control patterns from the nervous system that build muscles functionally— the way we use them in sports and in life.

Most kettlebell movements start from the basic athletic position, with knees bent, hips back, arms forward, chest out, and spine and head neutral. Kettlebell exercises build strength from this position, which transfers to almost everything we do. Basic kettlebell exercises will give you a pile driver golf swing, increase your vertical jump, and boost strength and power that will transfer to any movement.

Unlike dumbbells, the kettlebell weight is located at the end of the handle, instead of on either side of it. The kettlebell design allows you to do high-speed ballistic exercises with a pendulum-like action. Many kettlebell exercises, such as swings, snatches, and cleans require high-speed eccentric muscle contractions, which produce surprisingly high muscle forces. High-speed eccentric training develops whole-body fitness rapidly, with little or no muscle soreness.

Even though kettlebell training has been around for more than 150 years, scientists are only beginning to study this remarkable form of exercise. Recently, Chico State biomechanics professor Dr. Chengtu Hsieh and I studied ground reaction forces during the principle kettlebell exercises— the one- and two-arm swing, and one-arm snatch. Most of the muscle loading occurred during the downward phase of the swing (eccentric phase). The weight of the kettlebell increased by four times during each swing, which is far greater than traditional weight training.

Kettlebell workouts involve few exercises and don’t take very long, but they’re not easy. Doing 5 to 6 sets of 20 or 30 kettlebell swings or snatches with minimal rest is like riding a bull at the rodeo. Your thighs, glutes, and abs burn as you try to control a pendulating weight moving at high speed. The muscles of your upper back, shoulders, chest, lower legs, and spine contract and relax to provide stability during these dynamic exercises. Kettlebells are for you if you want impressive results in a short time and are willing to work hard. Water aerobics, yoga, and step classes might be easier and more civilized, but they won’t turn you into a block of human steel the way kettlebells will.

The principal kettlebell exercises— the swing and one-arm snatch— are highly ballistic and involve concentric, eccentric, and static muscle contractions from different muscle groups. Muscles contract concentrically when they shorten as they exert force. Examples include the active phase of standard exercises such as the biceps curl and bench press. Muscles contract eccentrically when they lengthen as they exert force. Lowering the weight to the chest during a bench press is an example of an eccentric movement. Static contractions develop force without changing muscle length. During any motion, some muscles contract concentrically to cause the movement; other muscles contract eccentrically to control the movement; while other muscles contract statically to stabilize the motion. Most standard weight training programs concentrate on concentric contractions and largely ignore eccentric and static contractions.

Muscles can exert much more force eccentrically than concentrically. Also, the absolute force during eccentric contractions increases with velocity. In other words, you can overload muscles better training at high speeds then at slower speeds. Kettlebell training works the muscles dynamically in a way that builds strength and fitness while minimizing joint loads.

High-speed ballistic kettlebell training involving concentric, eccentric, and static contractions increases muscle mass and strength at an incredibly fast rate. Canadian researchers, led by Tim Shepstone, found that high-speed training increased muscle cross-sectional area and the size of fast-twitch motor units (muscle fibers and their nerve) better than slow-speed training. High-speed contractions caused greater disruption at the cell level which promoted muscle protein synthesis and caused larger increases in muscle mass and strength.

Kettlebells build aerobic fitness and promote weight loss. Kettlebell workouts are closer to interval training than standard weight training. The principle exercises (two- and one-arm swings and one-arm snatches) are practiced continuously and intensely, using high reps. This causes whole-body stresses that more closely resemble repeated 400-meter sprints than standard weight training exercises (e.g., bench presses and squats). Kettlebell training creates metabolic stress that increases cell structures called mitochondria that build endurance and stress the heart so that it can pump more blood.

Kettlebell training programs promote weight loss. As discussed, many recent studies have shown the power of high-intensity interval training for increasing metabolic rate and reducing body fat. Kettlebell workouts are consistent with the kinds of exercises that produced rapid weight loss while maintaining muscle mass. Combining high-intensity interval training with kettlebells will build muscle mass and endurance quickly and effectively with a minimal time commitment. This program is not for wimps, but the pain doesn’t last long. You will be amazed by the results.

Pavel Tsatsouline, a former physical training instructor for the Soviet Special Forces and a nationally-ranked kettlebell competitor in the former Soviet Union, popularized kettlebell training in the United States. He elevated it from an obscure, quaint training method of ancient athletes to a wildly popular form of exercise that has applications for people ranging from elite athletes to elderly people in nursing homes (see www.dragondoor.com). He described the elegance of kettlebell training: “You do not need incredible amounts of gear or elaborate venues; just one bell, one man, and a lot of green grass.”

You don’t need a rack full of kettlebells to get a good workout— start with one. Pavel recommends the following kettlebells for men and women:

Choosing the Right Kettlebell
You	Your First Kettlebell	Recommended Set (after you get hooked)
Average Man	35 pounds	35, 44, 53, 70 pounds
Strong Man	44 pounds	44, 53, 70 pounds
Strength Athlete	53 pounds	53, 70, 88 pounds
Average Woman	18 pounds	18, 26, 35 pounds
Strong Woman	26 pounds	26, 35, 44 pounds