Would it be a good idea to do a 5X5 workout after circuit training?
No. A cardinal rule of fitness is do not mix programs on the same day. 5x5 is for strength training. You will be severely cutting yourself short by attempting this after a circuit. You simply will not be able to use the weight necessary in good form when you are fatigued from the circuit. I would go as far as saying don’t do circuit training at all when training for strength. You can’t combine workout goals (cutting vs strength) and expect to achieve the benefits of both. Actually you are diminishing your returns in both.The only sensible way to do this would be to do circuit training only a few days a week for several weeks or a few months to hit a specific body fat or weight goal – then do the 5 x 5 program to build strength (or vice versa). You simply cannot do both simultaneously and will be killing your gains in both programs.
Is HIIT the same as circuit training?
As I’ve noted before, High Intensity Interval Training seems to have morphed from it’s original parameters into whatever people want it to mean.So lets be specific. HIIT training is an “aerobic” form of exercise that involves intervals performed at specific heart-rate zones. It is not resistance training nor does one “work to exhaustion”. In fact, that would defeat the purpose.The idea is to work hard enough during the interval periods so that recovery is rapid and one can perform the next interval in good form.One needs must familiarize oneself with the aerobic training “Zones”:Heart Rate Training Zone CalculatorAnd also calculate one’s maximum heart-rate.The idea is to work from a baseline where one is maintaining the “aerobic training” heart rate. 65–75% of max. Then, for the length of the desired interval (15–60 seconds for most) the heart rate is driven to the 90% level.After the interval, one recovers (by slowing down whatever you’re doing) to the aerobic zone and then repeat.90% is considered optimal because it provides the desired training stress but is relatively easy to recover from. Ideally, the recovery period should be the same as the interval period.It does not matter what exercise form you use to achieve this. Any aerobic (“cardio” to use the slang) exercise will do. Run, cycle, stationary machines, whatever. Monitoring the heart rate is perhaps easier on a stationary machine; many incorporate. HRMs.One can work harder. The “Tabata” interval system involves harder, longer intervals. However, I always caution that this form of training is usually done by elite athletes in training. It may not be recommended or even safe for your “average Joe”.
What is circuit training and what are its benefits?
The basic idea of Circuit Training is creating a "circuit" - ie. a number of exercises. For example, I create a circuit for 30-45 minutes. I'll pick 4-5 exercises and perform them back-to-back for one round and repeat 4 or 5 times. I will take a rest in between (60 seconds). These exercises can really be anything you want, but a typical routine I will do is bench press, push-ups, squats, pull ups, sit-ups, and shoulder presses. You can manipulate the rest time or reps per exercise any way you want to make the exercise more or less intense. The benefit of doing circuit training is increased endurance, strength, cardio, weight loss, etc. It really helps to stimulate your metabolism as opposed to just running or doing weights the old school way. If you are doing circuit training the way it is meant, it will be intense and you will be gasping for air. Try to pick appropriate weights so you can handle a variety of reps (4-6, 8-12, 12-15, etc). It's a lot easier to see weight loss with circuit training and an easy way to build mass and stay cut.
Are there strength training programs design to maintain, not increase, strength?
There aren't any programs that are specifically designed to help you maintain strength. But any program that has you working at a volume or intensity that you've done before - or slightly below it - will lead to maintenance. That's because if you aren't doing more work than you did before (i.e. providing progressive overload), you're not getting stronger. But because it's a lot harder to build strength than it is to maintain it, continuing to train at previous workloads will allow you to maintain the strength levels you've already gained...at least for awhile.
Will strength and conditioning training twice a week be enough?
Enough for what? It really depends on your goals.Strength and conditioning are said together so often that people think they're one thing, but strength is different to conditioning.If you’re allowing for only two sessions a week, I highly recommend splitting them into separate workouts.See, conditioning is quite activity-specific. Conditioning for boxing is different to conditioning for sprinting.Likewise, strength training can refer to maximum strength, speed strength, or power. These are different qualities that require slightly different programming.For an all-round metabolic conditioning workout, I recommend a high-intensity interval training (HIIT) circuit.You could do this just with bodyweight exercises, but things like kettlebells, medicine balls, sandbells, and battle ropes are ideal. Pick a lighter weight that will allow you to do as many reps as possible (AMRAP) within a given time frame without reaching failure. This could be 20 seconds of work followed by 10 seconds of rest — the rest should scale with the interval.Set up a circuit of four to eight exercises to complete like this. Take a rest and do it again, for three to five rounds. The idea is to push yourself over your aerobic threshold repeatedly with short recovery windows. This will improve cardiovascular and muscle endurance.For the strength workout, you want an entirety different approach. Since you’re just doing one a week, it needs to be a total body workout consisting of an upper body push (bench press, overhead press, push up, dip), an upper body pull (bent-over row, pull up) and something for the legs (squat, lunge, deadlift).There are a ton of varities to all of these exercises — plenty to keep one busy. The deadlift is excellent because it works so many muscle groups and trains the hip hinge motion, which is vital for many sports and day to day activitiesTry to cycle the exercises every week and keep track of the load. The goal is to add weight regularly to see strength increase, although progress may be slow at just one session a week.The focus should be on fewer reps for more sets, with longer rests — something like 3 sets of 5 reps is ideal for beginners. You should be aiming for at least 80% of your maximum, as long as you've mastered the form — it really helps to have at least one session with a trainer.Hope this helps, all the best.