How to achieve your fastest weight

There is such a thing as your ‘fastest weight’ - if you’re a dedicated runner, you’ll probably already know this.

Speed and endurance depend on how fit and healthy you are, and how hydrated your body is. Regular training will result in losing weight over time - but knowing what your fastest weight is also extremely useful. You need to be light enough but your body needs to be resilient.

Achieving the right body weight - your fastest weight - will help you be both. Three months ago, we gave amateur runner Matt Smith a Marsden M-550 to help him find the perfect weight, tracking his progress as he did so. Here’s Matt’s story...

How do I know what my fastest weight is?

I’ve been a regular runner for 10 years. I entered my first competitive run - the Lincoln 10K - in 2009, and since then I’ve been determined to continuously improve my ability to achieve great times over long distances.

The peak of my achievements so far was completing the London Marathon in 2016. But it hasn’t meant I’ve reached my fitness peak. I am always looking for ways to tweak here or lose a few seconds there - marginal gains! - but it is only relatively recently that I began focusing more and more on weight.

Sticking to that perfect weight is important to me in order to reach what is best for my power to weight ratio. Finding your perfect weight takes time, and although I have occasionally checked how much i weigh over the past few years, it’s only since having the Marsden M-550 that I’ve tracked it more regularly.

It’s simply been a case of weighing myself a twice a week, keeping a record of my times (evening 10k runs, weekend 5k Parkruns and the odd competitive 10k, half marathon or marathon).

What is my fastest weight?

For my best results I have been in the category of 63-65kg. Going into competitions too light can lose the power that is required and also can affect stamina later on. Going too heavy means I cannot run as fast for prolonged periods. To compete effectively in 5k and 10k runs I tend to see the 64kg mark as around the perfect weight to perform with my body composition.

A typical week

My weekly routine is largely the same - last week is a good example of how I check, prep and train.

I started the week with a tempo 10k run on Sunday. I weighed in at 64.5kg that morning and both pre and post meals were high carb. This was to fuel a mid distance run and then fuel back up for the coming days. At time of 41.37 over my usual route was not a bad result, but too far off my p.b for the route (37.56) for my liking.

Monday and Tuesday were both steady 9k runs that were fuelled with low carb meals in order to ensure that I stayed within my weight category and burnt any excess weight through the activities.

Wednesday morning I weighed in at 64kg - my target for the week. There was no running on Wednesday, so a careful eating plan was needed in order to ensure I maintained my weight over the coming days.

Thursday was an 8k run, taking in several sprint sessions, which improves overall speed, and also encourages greater fat burning. This will also help with me having planned two upcoming recovery days. I will refuel with more calories after a more intense workout.

Friday I weighed in at my target 64kg. No running on Friday, and after a busy social weekend I was ready for another 10k run again on Sunday. That busy weekend did involve a few drinks and a slightly less structured diet plan, meaning on Sunday I was back to 64.5kg - I’m not sure whether it was the extra 500g or a mild hangover, but that run felt slightly more arduous than the earlier runs. A time of 41.59 was achieved, so work to do there.

My target is to stay at this weight until a week on Sunday when I race a 10k. Due to tapering down I will watch my diet and weight more carefully over the coming week.

Tips for achieving your fastest weight

The lighter you are, the more efficiently oxygen can be delivered through your body - less weight means oxygen doesn’t have to travel so far. Leaner bodies also burn carbohydrates more efficiently, and with less insulating fat tissue heat is dissipated faster.

For a runner, weight isn’t everything - but it’s a big thing.

You will only know your fastest weight through trial and error, and it will take time to find the weight you perform best at. Here are some tips for finding, and achieving, your fastest weight.

Plan a running diary

Have a weekly diary that ensures you run the same distances at the same time each week. Ensure the route is the same, or at least the terrain is the same each time.

Weigh yourself every week

This can be either be once a week at the same time - like a Monday morning, for example - or just before each run. Bear in mind that weight my fluctuate; it’s the overall trends that you need to concentrate on, and it’s better - at least to begin with - to compare month to month rather than week to week.

Keep a record of your times

There are numerous smartphone apps out there to make this easier. Keep a diary of each time you record alongside the weight you were at that time.

Tweak your diet to suit

What you eat will have more impact on your weight than running. Once you have your routine, start planning meals to suit.

Weighing scales for runners

For a simple yet dependable (and not to mention accurate!) weighing scale, chose the Marsden M-550. This is the scale that Matt used. It’s the perfect scale for your bathroom, ands since it’s Class III Approved, you know you can rely on the readings.

If you want to know more than just your body weight, opt for the Marsden MBF-6000 or MBF-6010. These body composition scales offer everything from Fat Mass and Muscle Mass to Basal Metabolic Rate, Metabolic Age and Skeletal Muscle Index measurements. Since muscle weighs more than fat, you can get a much clearer idea of, for example, your fat to muscle composition. See all of Marsden’s body composition scales here.

For more information about achieving your fastest weight, read this blog post. Get in touch with Marsden here if you have any questions about weighing scales.