Over all my assessment of this exercise regimen is that
-it is great if you are the type who needs a structured program,
-great for cardio,
-over all, most likely not the best for strength training.
F45 is a 45 minute regimented training that is divided into two types of classes: cardio and strength conditioning (training). In each class you spend a few minutes warming up then go through a set number of stations, doing 2 - 3 thirty second continuous movement exercises (interspersed with fifteen second rest periods).
For cardio, this is probably one of the best 45 minute trainings you may do - certainly will burn more calories and get your heart beat racing more so than say, running or biking. The only workouts I've done in the past that would be more rigorous, again, speaking just cardio wise, would be sustained martial arts exercises, punching, kicking, jumping, over the same time period. When I used to train martial arts my thick cotton uniform would sometimes end up drenched in sweat. The F45 program is a notch below that, but still very rigorous.
So if you're looking to burn calories or build cardio endurance heart beat wise, F45 is a top notch choice.
Where F45 isn't so optimal is in strength training. This is for two reasons:
(1) F45 training doesn't necessarily lead to optimal strength conditioning because it doesn't lead to guaranteed muscle failure during each set.
When it comes to lifting weights, or any kind of strength conditioning, while simply moving the weights or encountering resistance for a number of repetitions will build strength, it is momentary muscular failure - that last rep where you can't even complete the repetition, that tears the muscle and prompts it to rebuild stronger. Scientifically, tests have shown that following momentary muscular failure and the resultant muscle tearing, the muscle rebuilds stronger some 24 - 48 hours after the event.
So, when it comes to strength conditioning, simply moving the weights or encountering resistant may increase strength, but hitting momentary muscular failure in your set is what really builds strength.
In traditional weight lifting, the way to do it is to use the correct weight to hit muscular failure somewhere between 6 - 10 repetitions, rest, and then do it again, for a total of at least 3 sets, with perhaps 1 of those sets being a warm up, a warm up being defined as a set where you do not hit muscular failure.
With F45, you have a high probability of every single set you do being nothing more than the equivalent of a warm up.
The chances of hitting momentary muscular failure in a rushed set regulated only by time, are minimal. In F45 you have say thirty seconds to jump in there and move the weights around. Are you going to hit muscular failure even once during that set? Maybe, maybe not. It depends on whether you use sufficient weight and whether you push yourself to the point of failure, and whether time doesn't run out during whatever set you are doing before you hit that point.
Certainly picking an arbitrary point to end your set - such as the elapsing of a set time - is Not the way to ensure hitting momentary muscular failure. Momentary muscular failure is hit as a function of maxing out the weight versus repetitions, it is not based on a rigid number of reps, certainly not based on a rigid passage of time.
(2) The second reason F45 training is not suited for strength conditioning is the increased likelihood of injury.
There are exercises that even I, who have been lifting heavy weights since the age of 18, no longer do, such as bent over rows. Weighted squats if not done properly and in perfect form may also lead to injury.
The chances of injury in this rush rush do as many sets as you can in thirty seconds then run to the next station and hurry up again, are much higher than if you were doing weight training at a regular gym, without any concern for the running of the clock.
As well, although yes there are two instructors going around correcting form, we're talking about classes of up to 35 people with only two instructors where participants are in a hurry to beat the clock - I'd say that the chances that participants will do something wrong, incorrect form, during class are much higher than that they will do things perfectly, and incorrect form times weights are what lead to injuries.
Stepping back from this criticism, the bottom line is that if you're the type who simply won't do it unless forced or guided, then perhaps F45 is for you. F45 is also great for cardio, calorie burning (weight loss - although I can't imagine an out of shape overweight person really being able to keep up with the pace in the first place).
F45 is less great for strength conditioning, where the chances of injury are relatively high compared to traditional relaxed pace weight lifting in a gym, and the muscles are simply not going to get hit to momentary muscular failure enough to ensure optimal strength increase. read more