100K Training Plan: Complete Guide to Your First Ultra

Our 100k Training Plan – Just Finish is designed for runners who want to comfortably complete their 100k, without focusing on speed or finishing time.

Once you go beyond marathon distance and stray into ultra territory, the training strategies and advice vary an incredible amount.   

This 100k training plan just finish plan was initially developed by pulling strategies from a few sources, and has been refined by myself and several other ultra-runners.

Keep scrolling to access the 100km plan for free in PDF or customizable Google Sheets format in both miles or kilometers.

Related: How Long Is A 100k in Miles? 100k Training Guide

100k Training Plan – Just Finish: Essential Info

Who Is It For?:

Our Just Finish training plans are for runners who simply want to complete the event.

If you don’t want to spend all your free time training, and have no specific finishing time in mind, this is the plan for you.

Our Just Finish training plans usually have more rest days and very little speed work (if any); they’re designed to condition your body to complete the distance, but not more.

The 100k training program Just Finish is ideal for beginner ultra runners, or for runners with busy lives!

Find out other ultramarathon training plans – for different goals and ability levels – by clicking here.

How Long?: 

Six months // 24 weeks.

How Many Days Per Week?:

The majority of this plan features 4 or 5 days of training per week.

Training Breakdown: What Will Your Weekly Schedule Consist Of?

Speed Work

One optional day of speed work is included in the schedule; this is to improve your base running speed and your running economy. It’s not considered mandatory; prioritise long runs over all other runs.

Time On Your Feet

This is paramount – more important than speed or miles. It’s also the biggest commitment you’ll have to give for your 100km preparation. Your body has to get used to being on your feet for hours on end, so it holds up well come race day. 

Hence the huge amount of miles included in this plan. This can mean committing serious chunks of your life (weekends) to running.  

Cross Training

An 100km run is all about endurance, and muscular strength makes you an endurance animal. Many runners can get by with marathon-length runs by doing only running training.  

But once you are on your legs for several hours at a time, having some core strength really helps you keep your form and fuels your endurance. Remember – your whole body is active while running, not just your legs.  

I highly recommend doing cross training once per week (more if you manage), focussing on the upper body. If you only have time for one cross-training session, focus on your legs with lunges, squats and stretching – your body will thank you when you’re 10hrs into the race.

Cross-training also improves your cardiovascular health and strengthens some of the muscles weakened through running, thereby reducing your chance of injury. Other recommended cross-training exercises include bodyweight exercises, light gym work, swimming, yoga, pilates, and cycling.

Long Runs

Just like marathon prep, you should be factoring in one long, slow run every weekend. As a minimum, you want to have completed at least one 30+ mile run (50km) before your 100km. 

This 100km program features two 30 milers, and a single 37 miler.

Another worthwhile training technique is back-to-backs. This is running two long runs on consecutive days. This technique gets your body used to running on tired legs.  

Tapering For 100k

Tapering is the age-old marathon training technique of letting your training peak 4 weeks before your race and gradually backing off.  It’s a nice rule of thumb that means you’ve given yourself plenty of time for preparation.

Tapering minimises the risk of injury prior to the race and means you should arrive at the start line in the best possible condition. 

However, you’ll often find that it’s harder to apply such a rigid structure to ultra-marathon training. Many seasoned ultra-runners barely taper at all – they might just relax a bit more in the week leading up to the event.

Check Out The Premium Version of The 100k Just Finish Ultramarathon Training Plan . . .

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