Getting better muscle toning and building results isn't always a matter of lifting heavier weights or performing more repetitions.

You don't have to pour over published research or earn a degree in exercise physiology for the sake of better, more efficient workouts. Here are secrets that will help you get twice as much out of your strength-training efforts.

Double-Duty Tip #1: Try compound exercises.

Just like compound words that combine two words to form a new, more complex one, compound exercises join two exercises that form a more effective new one.

A wall sit with lateral dumbbell raise is one example. It combines two movements (the squat and lateral raise) into a single exercise. They differ from isolation exercises, which involve one movement.

Why it works: Compound exercises train multiple muscle systems to work together rather than isolating them to work independently. Since that's how we tend to move in real life, it's a more functional way to strength train.

Compound exercises can also help you get better results. They recruit more muscle fibers than isolation exercises, allowing you to lift heavier weights. They'll also save you time. Why do three sets of squats and three sets of overhead presses (six total sets) when you can put the two together and finish in half the time?

How to do it: Amplify your results in half the time by doubling up lower body exercises such as lunges and squats with upper body moves. A few examples to get you started include side lunges with dumbbell press or dumbbell chest presses on a stability ball (to help work your core and balance) instead of a bench.

Remember to start with simple movements and light weights to develop proper form and technique. You can add weight and complexity over time as your body adapts to this timesaving workout strategy.

Double-Duty Tip #2: Skip the workout machines.

With a few sets of dumbbells (free weights), you can target every muscle group in your body without wasting time moving from machine to machine at the gym or switching between various pieces of equipment. It doesn't take much space to complete a dumbbell circuit either.

Why it works: Dumbbells help you develop power, strength, and endurance. In addition, they activate greater numbers of muscle fibers than exercise machines do (because machines passively hold your body I place), which doesn't require work on your part.

You have to work harder to balance free weights yourself and maintain proper form and posture while performing each exercise. Dumbbells also help you achieve better balance and symmetry between both sides of the body; they demand your weak side to perform work unassisted by the dominant side. This forces both sides of your body to develop at the same rate. Dumbbells are a timesaving gem with minimal financial cost.

How to do it: For every gym machine exercise, there is a dumbbell equivalent. Chat to your trainer or email me for the examples of these exercises.

Double-Duty Tip #3: One side is better than two.

It may be counterintuitive to think that performing an exercise using just one side of your body at a time (one-sided exercises, also called "unilateral" training) would give you better results in less time, but stick with me here.

A few common examples of unilateral exercises include single leg squats, one arm dumbbell rows and single arm lateral raises with a band.

Why it works: Not only do unilaterally trained muscles produce more force, but there are also other benefits to one-sided training that help you get more results for less time in the gym.

For example, one-sided training can improve core strength by recruiting muscles of the lower back and abdomen to maintain posture, balance and coordination during each exercise. In addition, this technique thoroughly trains your stabiliser muscles, which create a solid body framework especially at the core, hip joints, and shoulders.

How to do it: Double your results by combining one-sided training to both your upper and lower limbs at the same time. For example, perform a single arm dumbbell curl while standing on one leg.

Another method to obtain twice the results is to perform a single arm chest press on a stability ball. The possibilities are endless, so be creative?just be sure to focus your creativity to one side of your body.

The Best of the Rest: More Tips for Strength-Training Efficiency

Add exercises between sets. This efficient approach can cut your workout time by 10-15 percent. Allow yourself 60 seconds between sets and use this time to train other muscle groups such as the abdominals and lower back. You can also spend this time stretching.

Bring a water bottle. Not only does this strategy save time by reducing the number of trips to the water fountain, it helps keep you hydrated, thus increasing performance during the workout.

Work your core. If you have only five minutes to work out, focus on your abdominals ? arguably the most important muscles in the body. These muscles serve many functions: They protect the lower back, aid digestion and play a key role in maintaining posture.