The key to getting a good workout in less time is to be efficient at what you do when you're in the gym.  Seems obvious, right?  Well, don't be surprised when you see many knuckleheads in the gym who spend more time looking down at their smart phones rather than working out.  What a BIG waste of time.  If you want to get in a good workout in the gym, avoid the distraction of your iphone (other than programming your music) and spend more time focusing on your workout (i.e., exercises, sets, reps, etc.).  
     Here are some tips to keep you on the right track to get in and get out of the gym in less time:

• Keep your rest periods short between sets (e.g., 30 to 90s)--use a timer such as the Gymboss to stay honest on your rest intervals
• Avoid performing redundant exercises (e.g., do EITHER the T-bar rows or 1-arm dumbbell rows but NOT both)
• Step into the gym with your workout plan in hand to avoid time figuring what to do
• Avoid peak gym hours (i.e., 5-7 pm)--nothing worse than waiting for what seems like an eternity for someone to finish at the squat rack (!)
• Carry a water bottle with you while working out--avoid making trips to the water fountain
• Avoid chit-chat with others--wear headphones to convey the message that you're not in the gym for social hour
• Perform supersets--you can get a lot of work done in practically half the time
• Perform HIIT cardio--(e.g., alternate periods of 30s of high intensity with 1 min of lower intensity cardio)--this allows you to burn more calories in less time (e.g., 20 mins rather than 45 mins)  

    CrossFit is a trend that has been marketed heavily as a means to get stronger and more powerful via plyometric movements in a high-intensity, minimal-rest bootcamp environment in order to increase cardiorespiratory fitness, stamina, muscular strength and endurance, flexibility, power, speed, agility, balance, and coordination.  The workouts are short (i.e., 5 to 30 minutes) but are expected to occur 3 to 5 days per week.  Crossfit incorporates kettlebells, medicine balls, ropes, bodyweight exercises (e.g., pull-ups, push-ups, sit-ups, squats), gymnastics, and endurance exercise.  But the reality is that CrossFit is nothing more than a complex of compound pushing, pulling, running, rowing, and squatting movements that personal trainers have prescribed for many years.  
     What makes CrossFit more appealing to the masses is how the compound exercises (e.g., squats, pullups, pushups, sprints, rowing, push-presses, deadlifts, clean and jerks, etc.) have been structured into a bootcamp scenerio complete with minimal rest between exercises.  We live in an environment in which the consumer has a very short attention span and very little free time.  Hence the appeal of CrossFit--it incorporates high-intensity, quick exercises that can be performed within 30 minutes.  
    Whether or not you should try CrossFit is entirely your decision to make although I should caution you to the risks involved in performing advanced exercises (read: multi-joint movements)--some of which are technically complex.  Unless you have experience in performing squats, deadlifts, and explosive, plyometric Olympic lifts such as cleans, jerks, snatches, etc., I strongly encourage you to learn the fundamentals of these exercises before trying CrossFit.  Not only are the exercises risky but performing them in a fatigued condition increases the risk of injury.  A cursory look at YouTube CrossFit video footage of participants attempting to perform these exercises is atrocious to say the least.  In many cases, the weight lifting techniques are horrible, substantially increasing injury risk.  
   
      Here are the pros of CrossFit:

• Variety of workouts to lessen the effect of boredom
• Competitive drive to achieve fitness goals
• Enjoyment which may increase adherence
• Improves overall functional movement

     Here are the cons of CrossFit:

• Lack of proper exercise guidance (i.e., correct form, range of motion, etc.) from a competent certified personal trainer

• Higher risk of injury (esp. joint) due to a lack of personalized recommendation for loading
• Presented as a "one size fits all" workout regimen without periodization or progressive overloading
• Does not track training progress (e.g., strength, power) due to non-repeating workout protocols
• Prescribes exercises which are in many cases randomized without consideration for needed muscle/joint recovery 

    
     If you're still not convinced that CrossFit is NOT for you, then by all means give it a shot.  There's no harm in trying and you might actually like it but be aware that CrossFit is NOT for everyone.

    Those cast-iron or steel balls which look like small cannonballs with a thick metal looped handle on top can be useful for working on joint flexibility as well as functional-type movements (e.g., deadlifts).  One of the key benefits of working with kettlebells is the possibility to work the entire body for a powerful and efficient workout.  Other benefits include increasing strength (including core strength), power, endurance, flexibility, mobility and cardiovascular capacity.  You can achieve a strenuous workout in less than thirty minutes.  
     Standard kettlebell exercises should incorporate four basic movements:  the press, the pull, the squat, and the deadlift.  Examples include shoulder press, bent-over row, sumo squat, and Romanian deadlift.  Swinging the kettlebell (e.g., single- or double-arm swings) is another example of a pulling movement that makes the kettlebell uniquely beneficial for training purposes.  The end result is the incorporation of more muscle groups, including your core muscles (i.e., abs, lower back, glutes, and hamstrings), being worked.  Studies have shown that using kettlebells can improve coordination and balance in addition to increased muscle strength and endurance.  By swinging one or two kettlebells, you will be able to target your hips, back, glutes, shoulders, and legs.  An additional benefit is increasing grip strength.
     If you minimize the rest periods between sets, you can also get a cardiovascular workout with kettlebells.  Be sure to start out with lighter weights in order to get a feel for the movements and an understanding of how to properly control the weights.  The risk of injury (i.e., torn muscle, tendon, ligament) increases greatly if the kettlebells are too heavy, are swung incorrectly (i.e., away from the sagittal plane) or are swung too strenuously.  Focus on using good form by improving your technique.  Sloppiness is a recipe for injury.  
     The benefits of kettlebell training include:

• Efficient, quick workout incorporating many fitness components (i.e., strength, endurance, power, flexibility, cardiovascular)
• Requires minimal space
• Relatively inexpensive
• Excellent way to condition your body for sports due to functional movements
• Ideal tool for gaining core strength

     The drawbacks of kettlebell training include:

• Limited weight capacity
• Fixed weights

Bottom line:  Kettlebells can be useful for anybody but should be utilized as a complement to your workout program rather than your exclusive workout program.  Kettlebells should be thought of as a tool in conjunction with dumbbells, barbells, machines, and cables as another means to enable yourself to gain strength, balance, coordination, endurance, and good cardiovascular conditioning.