Get your running shoes – the FNB Joburg 10K CITYRUN  is coming, and it’s got your name on it. Bear in mind that 10 kilometres is a competitive distance – so make sure you hit the starting line ready and raring to go. Try these workouts to ramp up your running endurance in time for 24 September.

Research from Canada and New Zealand reveals that different kinds of running deliver specific fitness benefits. Shorter intervals, for instance, increase your VO2 max (one measure of aerobic endurance), while longer sessions boost your “Qmax”, the volume of blood your heart can pump. Smart (and fast) guys take advantage of four key types of training – speedwork, threshold sessions, speed-stamina workouts and relaxed long runs – to race better and boost fitness. Even mara- thoners can benefit from lung-busting 100m dashes.

In fact, Tom Kloos, coach of the elite Bay Area Track Club, says that failing to mix up training is the biggest mistake he sees runners make. “The best improvement I’ve seen is with speedwork,” says Kloos, who’s also the track and cross-country coach at Saint Mary’s College in California. “It improves the way you move, your biomechanics and your running economy. That way you can run at race pace much more comfortably.” We’ll show you the science-based benefits of each kind of workout and how to best fit
it into your training.


WHAT IS IT? A 30-minute sprint session. This training improves your stride, recruits more fast-twitch muscles and builds your fitness quickly.

THE DETAILS: Warm up with a 1.5km jog followed by form drills: 15 seconds each of skips, butt kicks, knee raises and fast feet (hit the ground as rapidly as you can). Do 3 sets.

To prime your muscles for sprinting, do dynamic activation: 30 seconds of mountain climbers followed by climbing 20 steps (or 20 step- ups on a bench). Repeat. Now you’re ready for the speedwork: Do 30-, 40-, 50- and 60m all-out sprints from a standing start. Walk back for recovery. Then do 100m fast three times, but not quite at a full sprint. Jog back. To cool down, run a kilometre, progressing from a steady to a very easy pace.

Sprinting uses more fast-twitch muscle fibres than distance running does and teaches you good form too – that is, pumping your arms, keeping your head and chest up and driving your knees forward. If you understand how this motion propels you, then you’ll also recognise when you’re breaking form during a longer run, and know how to correct it. “You learn to run faster with less effort. That’s a win-win,” says Kloos.

THE DOWNSIDE? Sprints are hard on your joints. You’re pounding them with up to 700% of your body weight with every footstrike. At slower speeds, half your motion is powered by muscle contraction and half by the energy stored in your tendons, says Jay Dicharry, director of the Rep Lab in Oregon. Your feet spend about a quarter of a second on the ground when you run slowly and just an eighth of a second when you sprint. “You don’t have time for the stored elastic energy to help you out when you’re sprinting, so almost all the work comes from active muscle contraction,” he says. That’s why Kloos advises giving yourself 48 to 72 hours to recover from this training.


WHAT IS IT? Running for 30 to 60 minutes at your threshold pace – the speed you can maintain without breathing so hard that you need to slow down. It improves your aerobic capacity and helps you incinerate more kilojoules than other kinds of running, because you’re working at a higher intensity for a long period with no rest.

THE DETAILS: Run at your threshold pace for 6 to 8km. When this workout becomes easier, run up to 30 minutes more when training for a 10K or less and up to an hour more for longer races. Then work on increasing your pace.

There are various ways to figure out your thresh- old pace, says Kloos. You can go by feel: It should seem hard but still be manageable to maintain. (That’s why it’s crucial not to push the pace fresh out of the gate.) You can also use a running table: If you’ve done a 5K or 10K, enter your time in the McMillan Running training calculator (

A rule of thumb, he says, is to go slightly slower than your 10K race pace, or add 40 seconds to your per-km 5K pace. If you tend to lose focus partway through a session, run with a friend. It’s more fun and you can keep each other on pace. If you can talk to your friend but don’t really want to, your pace is about right, Kloos says. “Your breathing has to be at that level.”


WHAT IS IT? High-speed repetitions of 180 to
1 500m. This is the most physically demanding and mentally challenging kind of running, says Kloos. The payoff for your 45 minutes of suffering is a stronger heart and more stamina. Longer intervals increase your heart “contractility” (the force of each beat) as well as the density of the mitochondria (cellular power plants) in your legs.

THE DETAILS: Warm up by jogging at an easy pace for 1.5km. Then do these form drills: 15 seconds each of skips, butt kicks, knee raises and fast feet. Do 3 sets and then prep your muscles for sprinting. Do four 70m acceleration striders (increase your speed incrementally until you’re going fast but are still relaxed and not in a full sprint; walk back). The intervals: Do 8×500m with a 100m walk recovery. The pace should be the fastest you can maintain for the entire workout. The recovery walk should take the same time as the 500m run. To cool down, jog slowly for a kilometre or two.

Long intervals aren’t for the faint of heart, but they’re great for your ticker. A recent Finnish study found that this kind of high-intensity interval training increased VO2 max, heart rate variability (a good indicator of cardiac health) and muscle capillary density, all of which help move oxygen throughout your body so you can exercise harder for longer.

You also burn major kilojoules through excess postexercise oxygen consumption (Epoc). In other words, you work out so hard that you keep burning kilojoules even after the clock stops. But don’t overdo it. “Four to six of these speed-stamina workouts is all it takes before you’re maxing out the benefits,” says Kloos. He suggests adding them to your training regimen eight weeks before a race. Do one every other week or so – that’s four to six sessions total.


WHAT IS IT? A slow and steady run. These burn the most fat and increase your stamina. But they can be hard on your joints if you have poor form or weak legs, so work up to longer distances.

THE DETAILS: Run for an hour or longer at a pace that allows you to easily hold a conversation. If you get too winded, walk until you’re breathing easily. Then resume running.

Running at a lower intensity for long distances
is still the gold standard for endurance training. In fact, many elite athletes divide their training into 70% relaxed long runs, 10% threshold sessions and 20% sprints, says Alex Hutchinson, Runner’s World’s Sweat Science columnist. “This balances out the hard sessions that yield the swiftest gains with the easier ones that allow for recovery and continued improvement.” If you’re looking to become lean, emphasise long runs. At 60 minutes, your body starts to draw from fuels other than just your blood sugar; this process can help you lose fat faster,
says Kloos.


How often should you be completing each of these workouts? Pick your goal below for a custom training plan from Coach Kloos.


Use a two-week cycle and aim to do one of each workout every two weeks. On other days, do strength training. If you can run three times a week, add two relaxed long runs.


Use a two-week cycle, being sure to do all four workouts every two weeks. If you can run six times per cycle, base the extra runs on the time to race day: Six months out, add a relaxed long run and alternate between threshold sessions and speed-stamina workouts for your other extra workout. Three months: add a threshold session and alternate relaxed long runs and speed-stamina workouts. Two months: add speedwork; alternate threshold and relaxed runs.


Both plans work equally well for losing weight.