What are reps and sets? A Beginners Guide to Strength Training - Never Too Old to Lift (2025)

If you’re reading this post, you might feel confused by some of the language used in the gym.Don’t worry, you are not alone. Fitness and healthcare professionals often use these terms without ensuring you actually know what they mean.

I’m often asked some of the following questions:

• What do sets and reps mean?
• What does train till failure mean?
• What is meant by reps in reserve?
• If an exercise feels easy should I do more reps or add more weight?
• What rep range should I use?
• What is meant by hypertrophy vs strength?
• How many sets to build muscle?
• How long should I rest between sets?
• What is active rest?
• How many exercises should I do per workout?
• What are DOMS?

This post will cover all the questions above in more detail.

After reading this post you will feel more confident in being able to answer all ofthese questions and more.You’ll probably know more than most of the younger gym goers.

First, I will define what reps and sets mean in exercise.

What does reps mean? Areprefers to a repetition of an exercise. So, for example, you might perform 6 repetitions of an exercise before resting.

What do sets mean? Asetrefers to a group of repetitions (or reps) of that exercise. So, the group of 6 reps you just did before you had a rest would have been your 1^stset. You may go on to do a further group of 6 reps of that exercise, meaning that you will have done 2 sets of 6 reps.

One of the ways to gauge if you are close to training to failure is to record your reps in reserve.Especially when you first start to train, you’ll be unsure of how much weight you can lift safely.Most people tend to stay too safe and never challenge themselves enough, resulting in a lack of progress and not achieving your goals.

Reps in reserve are the number of repetitions you think you could have continued to do after you reach your target.

This brings us nicely onto the next question of whether you should do more reps of an exercise or add more weight.

What should you do if you complete 6 reps and you felt that you had 6 reps in reserve?

You could either:

• Do 6 more reps
• Add more weight/resistance to the exercise

If getting stronger is your main goal from being in the gym, then you should aim to add more weight/resistance.This would then bring the number of reps in reserve down until you are able to train to failure.

Remember training to failure should mean you have 0 reps in reserve.

You can manipulate the sets and reps you do during your workout along with the amount of weight or resistance used. This manipulation of set and reps will result in working towards different goals.

The main goals within strength or resistance training are to increase:

It is generally considered that for each goal, the number of reps you should be aiming for are as follows:

Strength: 1-5 reps

Hypertrophy: 8-12 reps

Endurance: 12-15+ reps

Remember, to achieve your goal, you should aim to train to failure at the target number of reps you are aiming for.You should have 0 reps in reserve.

Finishing on 5 reps with 10 reps in reserve would not result in you achieving your goal.In this case you would need to add more weight.

As mentioned above, strength is the ability of a muscle to produce force, whilst hypertrophy refers to the size of the muscle.

A lot of people tend to naturally train in the hypertrophy range (8-12 reps) because they want to stay safe and are scared of using more weight.

When training for hypertrophy you will get some strength gains but these will be less than if you increased the weight so that failure occurred in the strength rep range.It all comes down to your workout goals.

Don’t you want to be efficient and use the time spent working out to achieve you goals sooner?

If you’re reading this blog, it is likely that you are over the age of 60. With that in mind, I would suggest that your initial goal is strength.

Remember, as you get older you naturally lose muscle mass and strength.

This is referred to as sarcopenia.

You can prevent and even reverse the effects of sarcopenia by training specifically for the goal of muscle strength.

You want to ensure that as you get older you have the strength to:

• Playing with your grandchildren.
• Lift and carry the shopping bags into the house.
• Climb a ladder to get into the loft.
• Continue to play golf, tennis, squash, etc.
• Go on hill walking holidays.
• Do everything you need to in the garden.
• Anything else that you can currently do but might be taking for granted.

My existing clients tell me that they would rather achieve these functional tasks than to have bigger looking muscles (for aesthetic reasons). If this is the case you should aim to progressively increase the weight used to reach failure within 5 repetitions.

However, your goal might to have bigger muscles. This is absolutely fine, but remember you should be looking to train in the hypertrophy rep range (8-12)

You will have your own reasons for working out and I want to give you the knowledge to be able to create a program that will meet your individual goals.

This will depend on what your goal is.

If are working out just because you know that you should do strength training to prevent muscle loss, you might only want to do the minimum needed.

However, you might have a more specific goal that you’re working towards that you want to achieve in the most efficient way.

It is generally considered that 25-45 reps per muscle group, per week, is the range you should aim for.There is no specific scientific evidence to state how this is split, but I would suggest 2-3 sessions per week.

The 2-3 Sessions per week is in keeping with the UK Chief Medical Officers’ Physical Activity Guidelines. This states that all adults should aim for at least 2 sessions of muscle strengthening exercises per week.

To read my post on exercise vs physical activity,Click Here.

As indicated at the start of this post, this is aimed at helping those new to strength training.If you have been training for years and are looking for a more comprehensive plan, there are more specific weekly routines that you can incorporate.

I will not go into that here. However, if you would like a more in depth insight into this topic, I highly recommend you check out this post from the Get Back to Sport S&C blog.

When you finish your 1^stset of an exercise, regardless of how many reps you performed, you should have aimed to train to failure.

If you jump straight into a second set without any rest, you will have effectively merged the two sets together to complete one longer set.In this case you are no longer in your target rep range and not achieving your goals.

It is important that you rest between sets so that you are performing multiple distinct sets rather than one longer set.It is generally recommended that the rest period between sets is 2-3 minutes.

3 minutes is a long time to sit and do nothing whilst you wait for your muscles to recover for the next set.

If you do that between every set, you’ll have spent more time resting in the gym than actually doing the exercises.

For that reason I introduce the term ‘active rest’.You only need to rest the muscle group that you have just taken to failure.I recommend using that time to perform a second exercise that utilises a different group of muscles.

By the time you have completed that exercise the muscles from your first exercise will have almost had time to rest sufficiently before the second set.

This will make your time in the gym far more efficient.

Once again this is dependent on several factors.You have to consider the goals that you want to achieve, the time you have available per workout and the number of workouts you plan to do per week.

As a starting point I suggest doing around 4-5 exercises that challenge different muscle groups and functional movements.

Click Here, for more information on the 7 Functional Movements and how to progress, regress and adapt them around pain.

If you want a more personalised plan it is worth seeing a strength and conditioning coach, physiotherapist or any other form of specialist who has an interest in strength and conditioning.

It is worth noting that if you are new to strength training, you are very likely to experience DOMS.DOMS is an acronym for delayed onset muscle soreness.

You are likely to feel an ache in your muscles (those that were targeted in your workout).This generally starts between 24-48 hours following your workout and can last several days.

The newer you are to exercise, the more severe and longer the ache tends to last.The more experienced you become the less intense the DOMS becomes.

This nothing to worry about and is a good sign that you have worked the muscles sufficiently to illicit a positive response.I see several people that are new to exercise become concerned and disheartened by the DOMS response.

There are many gym goers out there that are disappointed if they don’t experience DOMS following a workout.

If you are new to exercise (or are returning after a long hiatus) I recommend easing into you target rep range.Spend some time getting confident with the movement patterns and establishing a routine.

Trying to lift too much weight too early may result in you experiencing pain. This post on Load Tolerance explains this concept in more detail.

After having established your goals and motivations for starting I would then pick 4 exercises from the 7 functional movements.

In the sessions within the first week, work towards 3 sets of 15 reps.By the end of that week, try to find a weight that results in you having no reps in reserve after the 15^threp.This is your 15 rep maximum.

Once your 15 rep max is established, you can progress over the course of 12 weeks to reach your 5 rep max (no reps in reserve after your 5^threp).

(This is the case if increased muscle strength is your primary goal).

A 12 week program might look like this:

This is a program I use for people I see who are new to strength training.If you are already experienced in the gym, this might look different for you.Find someone who can help you create a program to meet your goals.

Please note I said someone who willhelp youto create a plan rather than make one for you.I tend to find your compliance and motivation will be better if you had a part to play in the planning phase.

If you are currently carrying an injury or have any health complaints, then I urge you to go and seek out relevant medical attention prior to starting any strength training.

It doesn’t mean you can’t start to train.You will just need to learn to adapt the exercises around your injury in the early stages.The strength training is often part of the treatment rather than something that should be avoided.

I’ve tried to be as comprehensive as possible in this post and answer as many of the commonly asked questions that I get in the clinic.

Please do not hesitate to contact me if you have a question that you would like answered.Either comment below with your query or send me an emailchris@nevertoooldtolift.com