By: Asim Syed MD, Kyair Smith MD, Jonathan Kahan MD

What you need to know:

Exercise is the greatest medicine available. The ability to exercise is more important than any other health factor and is the most important action you can take to improve your health.
Our goal is to improve health span, which we use VO2 Max as a surrogate for. Training this way breaks down into weight lifting/resistance training and cardio. Cardio further breaks down into base (zone 2) training and high intensity interval training (HIIT) at a ratio of 75/25.
All the specifics are less important than consistency. If you exercise regularly with effort, the rest makes very little difference, you will see vast improvements in your life and health.

What is our goal?

Our goal with exercise is to improve your health span, which is the length of time that a person is healthy, not just “alive”. We are not training for a specific sport. We are training for you to keep up with your children, optimally perform at work, being present for your family, friends and significant others, and travelling/living out your dreams even deep into retirement. Note that there are certain conditions where this plan will need to be modified, check with your doctor first.

How can I measure this?

We use VO2 Max as a surrogate for exercise capacity and health span. VO2 Max is the maximum rate of oxygen your body can use during exercise measured in milliliters of oxygen per kilogram of body weight per minute (mL/kg/min)27. Your body uses oxygen to create ATP (adenosine triphosphate) which is the energy molecule of all life processes. A higher VO2 Max means that you are able to handle more activities that require oxygen.

Why care about VO2 Max?

The people with the highest VO2 Max are also the people who live the longest and live with the best quality of life. In a study done of over 100,000 patients, VO2 Max was directly and inversely correlated with all-cause mortality.12 This amounted to an 80%(!!!) reduction in all-cause mortality between the top 2% and bottom 25% of patients (elite vs low).12 Note this effect was more than smokers vs. nonsmokers. This is the number one metric that you have control over that can drastically affect your health span.

How to Measure VO2 Max?

The gold standard approach is to measure using a CPET (cardiopulmonary exercise test). This is where you run on a treadmill with a closed mask system. However, the smart watches are fairly accurate and can track your VO2 Max overtime. We recommend purchasing one (see social for other reasons) in order to follow this important metric. Another way to test is the Cooper test, where you record the maximum distance you are able to cover on a track/treadmill over 12 minutes (do your best!). Then use the formula VO2max = (35.97 x miles) - 11.29 and compare to your age/sex chart below.

Figure 1: VO2 max chart for different genders and age.26

Who has the highest VO2 Max?

The people with the highest VO2 Max are endurance athletes, eg. cross country skiers, marathon runners, cyclists.28 We will copy their training in order to maximize our VO2 Max and therefore our health span. Note also there are two ways based on the equation to improve your VO2 Max: either improve your oxygen utilization efficiency or lose weight.

How do they train?

The best endurance athletes in the world train in the following way: A. Weightlifting/resistance training with a mixture of B. 75% base (Zone 2) cardio and C. 25% HIIT training (High Intensity Interval Training).31 These will be explored in depth below.

A. Weightlifting

Why should I weight lift/perform resistance training (RT)?

Resistance training (RT) can approximately reduce all-cause mortality by 15% and lower risk of CVD by 17% when compared with those who report no RT.11 However, less than 20% of adults age 45 and over (and <15% of women) perform any RT31. This number should be closer to 100%. It reduces blood pressure and improves lipid profiles, as well as enhances our insulin sensitivity (muscles are sinks for sugar and are the main way we regulate blood glucose). In addition, our muscles require a lot of energy to maintain their mass, leading to improved energy balance throughout the day (Muscles handle about 80% of our blood sugar, liver is 20%). Muscle mass is directly correlated with all-cause mortality, independence, performance in all capacities including mental, and cardiovascular mortality.13 For this section, we consider weightlifting, resistance training and calisthenics (body weight resistance training) the same in terms of benefits and risks and will use the terms interchangeably.

Isn’t weightlifting dangerous?

Weightlifting is safe.14 The following activities are more dangerous from risk of injury than weightlifting.

Figure 2: Injuries seen in different exercises per 100 hours14

How many times a week should I weight lift/perform resistance training?

You should aim to target each muscle group at least twice per week.11 Some exercises such as deadlifts target about 80% of your muscles, whereas a calf raise may target only one. Therefore, compound exercises (bench press, squats, deadlifts etc) are more efficient as they target multiple muscle groups at the same time. These can be performed effectively and safely with machines or with barbells/dumbbells. Kettlebells/Free weights are also safe however maybe more advanced than traditional weightlifting. You will obtain 90% of weight lifting benefits by just showing up consistently and putting in more effort than reading a newspaper. There are no differences in muscle hypertrophy (growth) using machines, free weights, or kettlebells, with machines being the easiest in terms of movements and joint protection. Note form is less important than getting the muscles used to the weight (people who focus on form get injured more often). You do not need fancy gyms or personal trainers, basic gyms are as cheap as $10-15 a month, have all the equipment you need and have free personal trainers to show you how to use it.

How should I warm up?

In general, a warmup for weightlifting can be minimal. We recommend just doing one set of 12 reps of lighter weights (see below), then another set of 6 reps of lighter weights than normal to warm up for the first exercise. After that you should train normally.29

How much weight should I use?

The rule of thumb is to start low and go slow. You should feel tension or stretch of the muscles during the exercise, a possible slight burning sensation (i.e. the lactic acid and other anaerobic metabolites), the “pump” of the muscle (water following increased blood flow) and a weakness/cramping sensation at the end. These are signs that the weight you are using is appropriate and that you are getting a good workout. It is important to note that less weight leads to less injury. Significant joint pain is bad, but you may experience some. Machines that only allow you to do one exercise are a great way to start. Most gyms will also offer free personal trainers who can show you how to begin weightlifting.

Another way to approach this is to imagine or attempt your one rep maximum per exercise and then aim for 60% of that to start with. Once you are comfortable with lighter weights, slow progression is key.

Figure 3. METS indicates metabolic equivalents of task; 1-RM, 1-repetition maximum; and RT, resistance training.11

How many sets/repetitions should I use

Repetitions are the quantities of a specific movement you do, such as 10 biceps curls. Sets are the number of ”blocks" of repetitions you do with resting in between eg. 3 sets of 10 biceps curls. There is no difference between 5-20 repetitions per exercise or 1-6 sets. In general, the higher the repetitions, the less weight per repetition you will use (leading to less injury, although this risk is low already), and the higher the number of sets, the less likely you are to have good form at the end of those sets. Weight loads that permit 8-12 repetitions are ideal for building both muscle mass and muscle endurance. For healthy adults, regimes of 8-10 different exercises involving major muscle groups, each exercise performed 3-4 sets of moderate intensity loads that permit 8-12 repetitions per set to volitional fatigue, ≥2 times per week, is effective for achieving muscular and cardiovascular benefits11. These exercises should be targeted to major muscle groups. Note also that thinking of a mantra such as “blank” in between alternating reps makes the time go faster and swearing while lifting has been shown to increase strength!32

Figure 4:Exercises targeting major muscle groups11. Deadlifts, pull ups and rows are missing from this figure for back exercises. These can be looked up online and should be incorporated into the above.

How long to rest between sets?

This will vary depending on the exercise, for example you may need to rest several minutes between squat sets while resting only a few seconds between calf raises. In general your pulse should be under 100 bpm (ie. not tachycardic or short of breath) and your muscles (including smaller muscles used for stabilization) should not feel fatigued.15 This is another great reason to buy a smartwatch or a heart rate monitor. A good strategy given the above is to do leg workouts last or exercises that leave you with a fast heart rate or short of breath.

Does it matter total body vs. upper/lower split etc?

In general it does not matter whether you do total body workouts, or upper body one day and lower body the next etc. The order of the workout should be pre planned however and should make sense eg. not doing 3 bicep exercises in a row. Also writing down the exercises, sets, reps and weights is a great way to track progress and to see where you are having issues. Think critically, increase weight slowly over time once you are comfortable with the set/rep burden and are not experiencing the signs of growth as above. Consistency is key.

I’ve been weightlifting for a few months, now what?

After you have learned the basics of weightlifting, most people enter into some form of periodization. Periodization is essentially a weight lifting plan to progress throughout the year. Note this is mainly to prevent boredom and there are no differences in outcomes between different schedules. RPE or rate of perceived exertion is a way to standardize how much weight to use. An RPE of 8-9 / 10 is very difficult while an RPE of 3-4 is easy. A macrocycle is typically a year, which is your overall weight lifting plan. A Mesocycle (or block) is typically 3 months and a microcycle is 2-4 weeks. There are different types of periodization. The most basic and most common is linear, where you gradually increase the intensity/volume of training overtime. The next form is nonlinear, where intensity and volume will change within a mesocycle. An example would be alternating high, moderate and low rep ranges with varying weights within a week. Lastly there is block periodization (most commonly used in training for a specific competition) which is divided into a hypertrophy block (high volume, moderate intensity), followed by a strength block (moderate volume, high intensity), a power block (low volume, very high intensity) and lastly an active recovery block (lower intensity/volume) right before a competition. Benefits of periodization include avoiding plateaus (and boredom!), reducing overtraining and optimizing performance. Every 8 weeks take one week off of weightlifting as a way to allow your body to recover. A sample of linear periodization is given in the appendix.

B. Cardio: base training (Zone 2) and High Intensity Interval Training

How much exercise should I get a week?

The real answer is however much is possible that fits your lifestyle. The minimum that is recommended from the American Heart Association to prevent CVD is 30 minutes, 5 times a week to reach at least 150 minutes per week of moderate exercise (base training aka zone 2), or 25 minutes, 3 times a week to reach at least 75 minutes per week of vigorous activity (HIIT). We will see below why combining both types is best.1 Aerobic exercise has favorable effects on lipid metabolism, cardiac remodeling, post-MI heart failure, insulin resistance, and endothelial function all of which contribute to the favorable effects on cardiovascular fitness and decrease the risk of developing CVD and may even decrease CVD progression.1,2

Overall however, we find the AHA recommendations to be inadequate for total weekly exercise time. The sweet spot for lesiure exercise appears to be one hour per day33.

Table showing various weekly exercise times compared with reductions in mortality. One hour/week or 420 minutes/week appears to maximize risk reduction

How do I know when to take a rest day?

Persistent soreness, especially in the same muscle groups for 48 to 72 hours, decline in exercise performance, feeling fatigued despite a good night's rest, poor sleep, feeling mildly sick, and irritability or mood changes are all signs that you may need to take a recovery day. However, rest days can also be active, including things like yoga, dynamic stretching, walking etc.

What are the heart rate zones?

Heart rate zones are based on a percentage of your maximum heart rate. There are five zones.

Table 1: Zone training description, definition and fuel source9

Maximum heart rate is calculated using the formula 220-Age. For example, a person who is 40 years old would have a max heart rate of 220-40=180.8,10

What is base training aka zone 2 training?

Base training (zone 2) is considered the “fat burning zone”. In reality, it is the threshold exercise level of which your body is using aerobic (oxygen) metabolism (ie. right before the body starts producing lactate). Base training helps improve VO2max by increasing the body's ability to oxidize free fatty acids (FFA) which causes them to become energy in the form of ATP (rather than becoming triglycerides or entering muscle cells to impair glucose tolerance). Additionally, base training increases the density of mitochondria in cells, which are the energy producing power houses for our bodies.

How do I tell I am in my base zone aka fat burning zone?

The most accurate way is to measure your lactate thresholds using multiple finger prick tests, however this is not recommended or ideal for most people. The best next way to tell is that it is the level of cardio where you can carry on a conversation but that the conversation is difficult (but not impossible). This is going to be about 60-70% of your maximum predicted heart rate (= 220 - your age).9,10 Smartwatches can detect it as well and have zones calibrated for each activity.

What is High Intensity Interval Training (HIIT)?

There is no standard definition for what HIIT training is. Basically, it is a period of near maximum exercise intensity followed by a period of rest or submaximal intensity. HIIT training improves the quality of mitochondria and increases our aerobic threshold as well, and therefore is the best way to increase VO2Max.17 Additionally, it is an extremely efficient way of exercising, meaning you can get a lot of work done in a short amount of time. Furthermore, many people find it more enjoyable than going at a slow steady pace for an extended period of time. There are multiple variations of HIIT including Tabata (2:1 intervals of high/low intensity), sprint intervals (near max for a short duration [seconds] in a 1:1 with recovery, repeated multiple times), EMOM (one minute on, one minute off etc.).18-20 Note it takes time for the heart rate to ramp up to near maximum intensity. Therefore, in classic HIIT, if you look at studies, it was near maximum intensity for 2-5 minutes! (not seconds) followed by a similar duration of recovery. The classic Norwegian 4x4 of high to low intensity is the best studied where you do 4 min of 85-95% of max heart rate then 3-4 min of recovery like jogging or walking then repeat 4 times with a 10 min warm up and cool down.21 HIIT training on a mitochondrial level improves the efficiency, and function of fatty acid oxidation as well, leading to improved VO2 max, and an afterburn of increased energy utilization.

Figure 5- Relationship between anaerobic and aerobic threshold28

What ratio of base to HIIT Training should we aim for?

Generally, when we follow what long distance swimmers, cyclists, marathon runners and cross-country skiers are doing, they are training at approximately 75-80% base training and 20-25% HIIT training.31 This way increases our mitochondrial density (with base training) while increasing efficiency and function (HIIT). It is difficult to perform more than 2 HIIT workouts a week, especially as we age. This protocol is to maximize the benefits of our VO2 Max triangle and to improve our health span, while minimizing risk of fatigue and injury.31

Feeling the burn? What is Excess Post-exercise Oxygen Consumption (EPOC) and how do I get it?

Excess Post-Exercise Oxygen Consumption (EPOC) refers to elevated oxygen uptake following high-intensity or prolonged exercise, and has been linked to favorable cardiovascular, weight and blood pressure outcomes. EPOC can last up to 24-48 hours! High intensity training (mainly) leads to increased need for ATP production (the energy unit of life) and therefore requires more calorie/oxygen demand. Sprints, circuit based resistance training and HIIT protocols are all highly effective for inducing EPOC, providing measurable benefits in terms of weight and blood pressure reduction, as well as overall CVD health.22 Of note, EPOC will get you an extra 30-50 kcal/day, whereas NEAT is the main driver of daily calorie consumption we can leverage (see obesity section).

Will exercise help me lose weight? Will it help me maintain weight loss?

Exercise is crucial for body composition, which is more important than overall weight. Exercise helps more with weight loss maintenance than weight loss itself. Dietary changes (see obesity section) are mandatory to lose weight, with exercise offering only modest benefit. However, once a patient has reached goal weight, exercise is a major factor for maintenance, and this has been shown in studies23. Regardless of weight, you should be exercising as above.

Other than VO2 Max, How does exercise affect my body?

See the appendix for all the hormones/chemical signals changed during exercise and their effects on the body. Studies show that a sedentary lifestyle, characterized by consistently low levels of physical activity, is now recognized as a leading contributor to poor cardiovascular health and predisposes patients to the development of cardiovascular disease. In fact, according to the Global Burden of Disease Study, a lack of physical activity can be attributed to almost 10% of premature death worldwide!22

Conversely, regular exercise and increased physical activity, even low levels, are associated with widespread health benefits and a significantly lower CVD risk. Increasing physical activity showed a reduction in all-cause mortality and may modestly increase life expectancy, an effect which is strongly linked to a decline in the risk of developing cardiovascular and respiratory diseases.23 Physical activity can improve insulin sensitivity, improve dyslipidemia, normalize elevated blood pressure, and improve overall health in many ways.6 Even in people with coronary artery disease, an increase in regular physical activity can improve VO2 max and, at high doses (~2,200 kcal burned/week), promote regression of atherosclerotic lesions34. There is evidence that high levels of non HDL-C which comprises LDL-C, IDL-C, VLDL-C and lipoprotein a (Lpa) have been associated with increased cardiovascular disease. A combination of aerobic and resistance exercise can help lower non HDL-C and hence reduce CAD risk. 4,5

Figure 6- Physiological effects of exercise on the body 8

What about Sauna? I have heard it is similar to moderate intensity exercise?

Beyond the relaxing benefits of saunas, new evidence suggests that sauna bathing has several cardiovascular benefits, which include reduction in the risk of high blood pressure, cardiovascular disease (CVD), stroke, neurocognitive diseases; respiratory illnesses; mortality; skin conditions; as well as pain in conditions such as rheumatic diseases and headache. The protocols however are tough, in that you need at least 20 minutes of sauna per session, at least 4 days a week, at a temperature of 80-100 degrees Celsius (176-212 F).3 Note at this time infrared (IR) saunas are unable to reach these temperatures, although there are a few studies showing similar benefits. Also note a hot bath/jacuzzi where the clavicle can be submerged may have similar benefits, although data from Japan has shown increased risk. Note at this time, the evidence for the benefit of cold plunges are lacking and more trials in this area are needed.

Similarly to exercise, sauna can lead to a reduction in blood pressure, improvement in endothelial function, reduction in oxidative stress and inflammation, beneficial modulation of the autonomic nervous system, improved lipid profile and arterial compliance, and cause improvement in the cardiorespiratory system.3 Therefore, sauna bathing may be a safer alternative for patients who are unable to do moderate physical activity. Increased frequency and duration of sauna bathing is associated with decreased risk of sudden cardiac death (SCD), fatal coronary heart disease and CVD, and all-cause mortality. Additionally, heat shock proteins are created which may be beneficial in cellular repair.

The one caveat is that most of this data comes from Finland, where Sauna is a way of life. The French Paradox (where red wine was associated with longevity secondary to extensive use in French culture and not because of the wine itself) has not been ruled out here. A second caveat is that there is an opportunity cost, where saunas are not as prevalent in the US, and some people may prefer to exercise regularly instead of enduring the heat. However, we find the evidence regarding sauna use and cardiovascular outcomes compelling, and would suggest if you have access to one, that you should consider incorporating the protocols into your exercise regime.

Key Points

Exercise is the magic bullet to living better and healthier. Consider it like hygiene. Move every day. There is no substitute.
Resistance training (weight lifting, calisthenics etc) is safe and should be the cornerstone of your exercise life.
Cardio is broken down into base and high intensity training. Aim for approx. 75/25 ratio of each per week.
VO2max is the number one modifiable risk factor for cardiovascular disease and longevity.

Exercise: The holy grail of health