Exercise Principles

FITT Principle

The four variables — frequency, intensity, time, and type — you can manipulate to structure a kettlebell training program and keep your body continually challenged.

The FITT Principle

FITT is an acronym that captures the key exercise variables you can manipulate to structure a kettlebell training program — keeping things constantly varied, staving off boredom, and keeping your body continually challenged.

The Four Variables

FITT applies to kettlebell training and to all other kinds of exercise. The elements offer guidelines for structuring your program.

Frequency

How often you exercise — workouts per week, exercises per workout, sets, or reps.

Intensity

How vigorously you train — measured by heart rate, load, or perceived exertion.

Time

How long the session lasts — total duration, set length, and tempo.

Type

What kind of exercise — kettlebell lifting combines strength, cardio, and mobility.

Frequency

Frequency describes how often you exercise. It can reflect the number of kettlebell workouts per week or month, the number of exercises per workout, the number of sets per exercise, or the number of repetitions per set. For example, if you exercise once a day for 4 days per week, your frequency is four workouts per week. If you exercise twice a day for 3 days per week, your frequency is six times per week.

In order to maintain a healthy body and to become fitter, a general recommendation is to exercise at least 4 days of the week.

Frequency and intensity have an inverse relationship. Together they equal your total volume of exercise — the total amount performed per unit of time (day, week, month). The more frequently you exercise, the less intense the workouts can be. The more intense the workouts, the less frequently you can exercise. This has to do with the effect of total volume on your body's ability to recover.

Intensity

Intensity refers to how vigorously you perform your kettlebell exercises — the amount of energy or effort needed to execute a particular exercise or session. It can be expressed in several ways.

Kettlebell lifting combines cardiorespiratory training with resistance training, so intensity can be measured as a function of either.

Measuring Cardiorespiratory Intensity

One simple way to measure intensity is to wear a heart rate monitor. Intensity is expressed as a percentage of maximal heart rate (MHR) in beats per minute (BPM). A more intense workout produces a higher heart rate; a less intense workout produces a lower one.

Calculating Maximal Heart Rate (MHR)A widely accepted formula:

Men: 220 − age
Women: 226 − age

Example: a 40-year-old man has an MHR of 180 bpm (220 − 40). A 40-year-old woman has an MHR of 186 bpm (226 − 40). Various percentages of your MHR give you the various training zones.

Finding Your Pulse

Immediately upon completing your training set, find your pulse by placing your index and middle fingers at one of two locations:

At the Neck

Just to the side and slightly above your Adam's apple (figure 3.1a).

At the Wrist

Lower portion of your wrist just above the palm (figure 3.1b).

Count how many beats occur in 15 seconds and multiply by 4 to get beats per minute (BPM). For example, 40 beats in 15 seconds = 160 BPM.

Figure 3.1 Finding your pulse: (a) at the neck or (b) at the wrist.

Figure 3.1 Finding your pulse: (a) at the neck or (b) at the wrist.

Heart Rate Training Zones

Warm-Up / Healthy Heart Zone — 50-60%

Best for beginners just starting a fitness program, and for warming up before more intense work. Associated with reduced body fat, lower blood pressure and cholesterol, and decreased degenerative heart conditions. Relatively safe due to mild intensity. Up to 85% of calories burned are fat, 10% carbohydrate, 5% protein.

Fitness / Fat-Burning Zone — 60-70%

Same health benefits as the healthy heart zone, but more intense and burns more total calories. Appropriate for more experienced exercisers who still want to emphasize fat-burning. Up to 85% calories from fat, 10% carbohydrate, 5% protein.

Endurance / Aerobic Zone — 70-80%

Improves cardiorespiratory function and can actually increase the size and strength of your heart. Optimal zone for endurance training; right for a more experienced lifter with good technique, health, and fitness. About 50% calories from fat, 50% carbohydrate, <1% protein.

Performance / Anaerobic Zone — 80-90%

Improves V̇O₂max — the maximal amount of oxygen the body can consume during exercise. Improves cardiorespiratory function and lactate tolerance, so you can better withstand fatigue. About 15% calories from fat, 85% carbohydrate, <1% protein.

Maximal Effort Zone — 90-100%

The all-out zone, sometimes called the red line. Burns the most calories, but most people can't sustain it for more than a few minutes. Best for highly conditioned athletes, typically during interval training that alternates short high-intensity bouts with longer moderate ones. About 10% calories from fat, 90% carbohydrate, <1% protein.

Which zone should I train in?

Beginners: Majority of workouts in the healthy heart zone to gradually develop aerobic fitness at manageable intensities.
After a few weeks: Begin incorporating more workouts in the fitness zone.
Experienced users: Stay in the fitness and endurance zones for most workouts.
Advanced / highly fit: Add more workouts in the performance zone with periodic sessions in the maximal zone.
Everyone: Always warm up in the healthy heart zone.

Measuring Resistance Intensity

Intensity can also refer to the amount of stress an exercise puts on your body — for example, the heaviness of the load. Lifting a 32-kilogram (71 lb) kettlebell is far more intense than lifting a 12-kilogram (26 lb) kettlebell for the same exercise.

Here intensity refers to a percentage of your repetition maximum (RM) — the maximum weight you can lift for a specific number of repetitions:

1RM — the maximal kettlebell you can lift for 1 rep
10RM — the heaviest kettlebell you can use to complete 10 reps

A heavier kettlebell will always be more intense than a lighter one.

Practical Programming

For general health and fitness, most kettlebell workouts should be of moderate intensity. Beginners are advised to use lighter weights at higher repetitions for safety — a lower-intensity effort for a longer duration. A more highly conditioned athlete will work at higher intensities by using progressively heavier kettlebells.

In a structured program, kettlebell users of all levels use varying intensity — some workouts moderate, some intense, some mild. This topic is covered in detail in chapter 9, Creating a Customized Fitness Program.

Monitor Intensity With RPEA useful subjective guide is the rating of perceived exertion (RPE) — a 1-to-10 scale, where 1 is very easy, 5 is moderately intense, and 10 is maximally intense.

Moderate workout: maintain RPE between 4 and 6
Easy workout: RPE in the range of 2 to 3

Intensity can be strenuous, moderate, or mild — and what is mild to one person may be quite intense to another. RPE depends on age, stress, rest, altitude, and current fitness. A high-level athlete may run a mile easily under 6 minutes; an office worker may struggle to run the same mile in under 10. The intensity is very different for each person.Even what you have eaten can affect RPE. Too much coffee or a heavy meal just before training can push RPE higher than training on an empty or only slightly full stomach. The more intense the exercise, the less intense the frequency and volume.

Time (Duration)

Time or duration is the length of time you are active in a single kettlebell lifting session — the terms are used interchangeably and usually expressed in minutes. In kettlebell lifting, there is also another important facet of time: tempo, speed, or pace — which affects the total volume of work performed in a given set.

Two Layers of Time

Total Workout Duration

Length of a single resistance training session — for example, 30 to 45 minutes start to finish.

Time Per Set

Length of an individual set — for example, 1 set of 30 reps may take 1 minute.

How Tempo Affects Volume

During some lifts, both time and tempo are calculated. Suppose you do a one-arm press for 2 minutes (1 minute per hand) with a 16-kilogram (35 lb) kettlebell:

Fast — 1 rep / 3s

20 reps/minute → 40 reps in 2 min → 635 kg (1,400 lb) of pressing volume.

Moderate — 1 rep / 4s

15 reps/minute → 30 reps in 2 min → 476 kg (1,050 lb) of pressing volume.

Slow — 1 rep / 5s

12 reps/minute → 24 reps in 2 min → 380 kg (840 lb) of pressing volume.

You'll become very familiar with this concept of tempo during your kettlebell workouts.

Take a look at table 3.1. In this table, four different kettlebell lifters each select a different load to train with. The numbers illustrate the workload for a single exercise set. Notice that by changing the variables of load, tempo, repetitions, and duration, we get workloads that are all within the same range of total volume.

Table 3.1 Kettlebell Training Volume Comparison

	Load	Tempo	Reps	Duration	Total Volume (Kg)
Lifter A	12 kg	24 RPM	96	4 min	1,152 kg
Lifter B	16 kg	18 RPM	72	4 min	1,152 kg
Lifter C	20 kg	20 RPM	60	3 min	1,200 kg
Lifter D	8 kg	25 RPM	150	6 min	1,200 kg

General health and fitness recommendation: kettlebell workouts of 30 minutes to 1 hour for at least 4 training days per week.This may seem like a lot, but consider that initially you'll be working at mild to moderate intensities. It's important for beginners to gradually build up frequency, intensity, and duration in order to stay injury free, allow for adequate recovery, and build confidence through setting and achieving manageable fitness goals.

Type

Type refers to the type of exercise you're doing — running, walking, kettlebell lifting, and so on. Our focus is on lifting kettlebells, a form of exercise that combines:

Cardiorespiratory Conditioning

Resistance Training

Mobility / Range of Motion

Because kettlebell training combines multiple facets of exercise, it is a time-efficient method for developing all-around fitness.

Targeting Specific Goals

Though kettlebells emphasize a combination of training goals, you can also use them in a way that focuses on one quality over the others.

Maximal Strength

Heavier kettlebells, lower repetitions.

Cardiorespiratory Endurance

Light kettlebells, higher repetitions to improve aerobic fitness.

Muscle Sculpting / Hypertrophy

Moderate-weight kettlebells for moderate repetitions, as in bodybuilding.

All-Around Fitness

A combination of light, moderate, and heavy kettlebells, with rep schemes ranging from high to moderate to low.

We're emphasizing the efficacy of kettlebells as a stand-alone fitness tool — you can achieve great improvement using only kettlebells. However, kettlebells also combine effectively with barbells, dumbbells, yoga, running, and other favorite activities.

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Exercise Principles

An introduction to the physiological principles and physical skills that govern every kettlebell training program.

Putting the FITT Principle to Work

How to apply the FITT variables — adapt through overload, adjust when progress stalls, and break plateaus with intensity, variation, rest, and nutrition.