For some, the season is well underway, so adding speed work now will help boost your performance. In order to race faster, we need to spend more time at race pace which will allow our bodies and brains to adapt to the effort. Your brain establishes a limit on how much pain it will endure. So the more time you can spend at that level the easier it will feel. Speed work is always a very delicate matter to bring up. Most athletes do not need it and if you enjoy racing ½ ironman events or longer it may not be worth the added recovery and risk of injury with the larger volume of training required. If you do race shorter events speed work will give you a huge boost, but you need to be cautious.
In order to improve fitness an athlete needs a mix of volume and intensity. Finding the proper mix for each athlete is the key. For many the ability to train long hours is not an option. So after about 3 weeks of hitting your maximum volume, that your lifestyle will allow, your body has adapted to the stress and will hit a plateau. So the next step is to train more, which most cannot do. The other option is to slowly add in some speed work, not to exceed 10-15% of total weekly volume. The key here is doing it slowly and allowing for extra rest. You will need to cut back volume first to ensure you absorb and recover from the speed sessions. Below are a few ideas to help incorporate speed into your training.
The goal of triathletes is to be able to swim the distance with as little energy expended as possible. Focusing on technique, proper navigation and drafting will translate into a good swim time. For many speed work may not even be necessary. Avoid trashing yourself in the pool and going into your bike or run sessions tired. If you are a front of the pack swimmer then you are familiar with speed work. The important issues will be proper race execution and using race pace simulation workouts. Race simulation sessions should prepare you for the all out race start, stop and go traffic at turns and bridging the gaps between swim packs.
For cycling the first thing to consider is bike fit. A comfortable bike will allow you to access your potential. Keep the speed workouts simple and after a warm-up start with 5 minutes at a zone 4 effort or a rate of perceived exertion (RPE) of 8 and add a few minutes each week to a max of 20 minutes. From there you can add in an extra interval and top out at 2 x20 minutes, with a 5 minute spin between. You can also do some criss cross workouts where you spend time bouncing between above race pace, race pace and below pace. This effort can last 10-20 minutes and will closely simulate actual race demands. Complete 1-2 speed sessions per week, but keep in mind you will also be doing run sessions so plan for recovery. Other things to consider are staying on the aero bars as much as possible, practicing your turns in order to carry more speed and watch your climbing pace. Try to spin the uphill and power over the crest and the downhill. However once you hit 27mph you are better off coasting and giving your legs a break. At that speed most of your energy is used to overcome wind resistance and very little translates into speed.
Running is the area where speed sessions need to be approached with extra caution. Start off with a few strides lasting 20-30 seconds at race pace with 1 minute rest between. Then add in short intervals such as 3 x 5 minutes in zone 4 or RPE of 8, with recovery lasting half of the interval time. This session is good to do once per week. If you feel like adding in another speed session you can try some cruise intervals where you hold close to race pace for periods lasting as long as 20 minutes, but build into this starting with just 5 minutes at first. It is always better to negative split your runs. This refers to running the 2nd half faster than the first. Also pay close attention to your running technique. Improving your technique alone could warrant some faster run times. Try to focus on run cadence shoot for 90 foot-strikes per minute and use your arms slightly, to help increase leg turnover. Make sure afterwards you devote extra time to stretching and maybe taking a 5-10 minute cold bath to decrease muscle soreness. Feel free to try barefoot running in the grass for a few minutes, running in front of a mirror or have a friend video tape you. Having an idea of how you look will allow you to mentally compare your form to faster runners.
Overall if you have been in the sport for a few years then speed work will be necessary. If you are new to the sport then focus on developing your aerobic capacity first and build strength through hill work or big gear work on the bike. This strength will translate well into your races and prepare your body for speed work in the years to come.