training | recovery

Page 1 2

And now, a one-legged study
We know this thanks to some excellent work carried out by the same research team which completed the radioisotope-recovery studies mentioned above. In their new investigation, eight men who had been carrying out regular resistance training for at least one year challenged the quadriceps muscles in just one of their legs by performing an exhausting series of knee extensions (eight sets of 10 reps at 85 percent of their one-repetition max). Immediately after these cruel exertions and again one hour later, they ingested either a Nutrasweet-dulcified placebo or a carbohydrate supplement containing one gram of glucose per kilogram of body weight. Since the men weighed about 75 kilograms each, this meant that they were taking in 300 calories of glucose right after the workout and also one hour later. Using their familiar radioisotope technique, the researchers looked at protein synthesis in both the exercised and unexercised legs (Effect of Glucose Supplement Timing on Protein Metabolism after Resistance Training, Journal of Applied Physiology, vol. 82(6), pp. 1882-1888, 1997).

As it turned out, protein synthesis was 36-per cent greater in the exercised leg, compared to the non-exercised leg, when the men took in glucose after the workout. In other words, the glucose was spiking protein synthesis in the exercise-traumatized leg but doing little for the leg which had not engaged in training. Meanwhile, the protein-synthesis rates in the exercised and unexercised legs of the placebo (no-carbohydrate) subjects were exactly the same! Since protein synthesis was not increased in the exercised leg when no glucose was taken on board, the processes associated with recovery were simply not initiated.

In addition, protein breakdown in the exercised legs was significantly lower when glucose was taken after the workout, compared to when placebo was swallowed. Thus, the ingestion of carbohydrate after the training sessions led to a much more positive protein balance in the athletes' bodies (protein balance is simply net protein synthesis minus protein destruction) and therefore was associated with a much more effective recovery.

You might be shocked to hear that protein breakdown would occur inside muscles after workouts. After all, why would muscle fibres want to tear themselves down following a bout of physical exertion? As it happens, this teardown is actually part of the remodelling process that muscle cells undergo after stress; damaged structures and enzymes are destroyed to make way for the new proteins which are about to be created. In addition, if fuel is not quickly supplied to the muscle, some proteins may be broken down and used for energy to keep the muscle cells viable until the empty energy depots are re-filled.


Carbs helping proteins
Why did carbs have such a positive impact on protein creation and why did they thwart protein destruction? They may have helped protein synthesis in a couple of key ways. First, the inflow of carbs may have simply given the muscle cells the necessary fuel to embark on the project of rebuilding. Using this carbohydrate energy, the muscles could grab amino acids from the bloodstream and kick-start the process of creating new proteins.

The carbs also boosted the production and release of insulin from the athletes' pancreases; plasma insulin values were three to eight times higher after the workout in the glucose group, compared to the placebo exercisers. Insulin is a noted anabolic (tissue-building) hormone which has a profound positive impact on protein synthesis in muscles. Insulin also tends to suppress protein breakdown.

The lessons from this research are important and obvious. By taking in ample amounts of carbohydrate immediately after training and again an hour later, athletes can get a head start on re-fueling their muscles after workouts, but they will also shape muscle-protein dynamics to favour protein creation and disfavour protein catabolism.

That is THE essential aspect of the recovery process. Athletes who fail to take carbohydrate following their workouts because of sheer negligence or a desire to shed weight are losing out in the long run, because their recovery processes are sub-optimal.


What about endurance athletes?
You might have noticed that both of the studies described above involved strength training. Would the same kind of results be obtained with endurance athletes? That is, do endurance-type workouts produce the protein-breakdown and protein-synthesis rates which are associated with strength sessions?
Research in this area is somewhat sparse, but a couple of years ago investigators at the University of Texas Medical Branch at Galveston studied seven female collegiate swimmers who carried out an interval workout consisting of 4600 total metres of swimming and on separate days a whole-body resistance-training session and also a super-session which combined the interval and strength workouts into one big bout of training (Muscle Protein Metabolism in Female Swimmers after a Combination of Resistance and Endurance Exercise, Journal of Applied Physiology, vol. 81(5), pp. 2034-2038, 1996).

The resistance workout was a tough one, consisting of three sets of six reps of bench presses at 80 per cent of the one-repetition max (1 RM), three sets of 10 reps at 65 per cent of 1 RM for military presses, side laterals, latissimus pulldowns, biceps curls, triceps pushdowns, leg presses, leg extensions, leg curls, hip abductions, and hip adductions, and two sets of 30 abdominal crunches. Rest between sets lasted for only 60 to 90 seconds.

Meanwhile, the endurance-training workout, which was typical of the kind of session conducted routinely by the collegiate swimmers, included a warm-up consisting of 500 metres of freestyle swimming, 200 metres of kicking, 200 metres of pulling, and 200 metres of technique drills. The main portion of the session was composed of 10 200-metre intervals at an intensity of 85 to 90 per cent of max heart rate, four 100-metre kick intervals, two sets of four 25-metre pull intervals, plus a 200-metre cool-down. Recovery swims between intervals accounted for the other 700 metres of swimming. As mentioned, the strength-plus-endurance workout simply combined the weight workout described above with this interval session.


What were the recoveries like?
As expected, protein synthesis was greatest after the combined resistance-interval workout, but interestingly enough protein creation tended to be about 35-per workout.

Thus, there's clear evidence that endurance-type work initiates a recovery process which may be even more dramatic than the restoration which occurs after a pile of tough resistance work. In addition, the rate of protein breakdown was about equal after the resistance and endurance-type interval training.

Given that swimming has none of the impact forces associated with running, those findings are very important for runners. One would expect that an intense running workout would produce even more protein breakdown than a swimming session and therefore necessitate even greater protein-synthesis rates following training. Thus, it appears that runners need to be especially scrupulous with their post-workout nutrition.

Overall, the lesson is that combining an endurance workout with a strength session seems to create a need for even more dramatic protein building, compared to performing a single session. Therefore, you need to be extremely vigilant with your recoveries on days when you complete both a strength and a quality endurance workout. That particular combination requires extra carbs after each session (or extra-extra carbohydrate if the two types of training are combined in one long workout), extra sleep during the night after the workouts, and a light day of work the next day.

Here are the key things to remember about recovery:
1. If you feel tired or sluggish on a particular day, don't train or train very, very easily: Your body is telling you that what you need is recovery, not hard work. If a quality workout was scheduled for the day, postpone it and carry it out the following day if you feel better, as long as you don't have another quality session scheduled for the day after that. Two quality sessions in a row are usually too much,especially if you have been experiencing above-normal fatigue.

2. To increase the number of quality workouts you carry out (ie, to avoid spending too much time recovering), try to use the 36-hour principle. For example, you could perform a quality workout Tuesday morning, another Wednesday evening, and a third intense session Friday morning, thus fitting three tough sessions into a time frame which usually accommodates just two. You could then take Saturday off and complete a long workout on Sunday.

3. To jump-start recovery and be kind to your muscle proteins, make sure you replenish yourself with ample amounts of carbohydrate shortly after your training sessions.

4. Ultimately, you are the best judge of how well you are recovering between workouts.

If you look forward to each week of training and approach your quality workouts with high energy and determination, you are recovering well perhaps too well, but it is better to recover too well than to recover poorly (recovering too well means you could probably carry out your difficult workouts sooner than you usually do). If you are feeling tired during many of your weekly workouts and your performance times are a bit off, it's quite likely that you can improve your performances not by working harder but by increasing the quality and quantity of your recovery.

Owen Anderson

« back